Hello,

This guide will show you how to achieve the necessary endings for the achievements.
You can also watch it as a novel, or just relax and enjoy the storyline!
There are 9 different ends that you can follow through a very detailed video of each.

I also added information where saving the game can give you a chance to complete several other endings much faster.
Beach Bounce is based on the idea that sticking to a girl and deny all the other's feelings will grant you a happy ending. Based on that idea, you can save, reload and try different alternatives.

There are other finals though, such as avoiding work grants you a bad ending, but your grandmother gets to live.
Yuuki can also get the resort for herself, especially if you cheat on her. Although none of them gives you achievements or any extra scene. Just plain simple text.

Have fun!

This video will help you unlock the "Happy End with Yuuki" achievement.
(Good End 1 = Together with Yuuki)

You can watch it as a novel, or just fallow the order below:


01 - I'm not big on sports.
02 - Offer to help.
03 - Tell her about Rei.
04 - Not really.
05 - Hell with it, sure.
06 - My Pleasure.
07 - Check the Indoor Pools.
08 - Sure Thing.
09 - Ask to come in.
10 - Take the Phone.
11 - Let's not drink anymore.
12 - Reception.
13 - I'll see about calling a repairman.
14 - Yuuki may need help.
15 - Pat her on the head.
16 - Reception.
17 - (Optional choice of location)
18 - Truth.
19 - Especially you.
20 - Start undressing.
21 - Sorry for the wait.
22 - Sorry I'm not in the mood.
23 - Tennis Courts.
24 - Keep it up.
25 - Yuuki.

Yuuki is easy to get as long as you always praise her personally and professionally. Do activities, but never let other girls get your feelings. In the end, just choose her.

This video will help you unlock the "Drinking devil" achievement.
(Bad End 1 = Ruined your life over a round of drinks)

You can watch it as a novel, or just fallow the order below:


(All previous actions don't really matter).

01 - Keep at it.
02 - More drinks?

If you want to grab this opportunity to end well with Mineko, just save after you chose "Keep at it".
If you go any further you'll be stuck with this end, even though still enjoy her ending... But Yuuki will hate your guts!

This video will help you unlock the "Happy End with Mineko" achievement.
(Good End 2 = Happy Ending with Mineko)

You can watch it as a novel, or just fallow the order below:


01 - I'm not big on sports / I'm Interested in sports too.
02 - Let it Go.
03 - Don't tell her about Rei.
04 - Not Really.
05 - Oh, -now- you want my help?
06 - It's what umi needs.
07 - Indoor Pools.
08 - I'm Broke.
09 - Hang up on them.
10 - Keep at it.
11 - Wow, you're hammered.
12 - Car Park.
13 - I'll see about calling a repairman.
14 - Yuuki may need help.
15 - Deflect.
16 - Reception.
17 - Car Park.
18 - Kiss her.
19 - Lies.
20 - Kiss her.
21 - Sorry i'm not in the mood.
22 - Sandy Beach.
23 - Mineko.

Mineko feels quite right. I mean she is the first girl to actually kiss us, and ask us on a date. The trick is to deny all the other girls, do activities and on her date, let her drink on the first option, but stop at the second event!

This video will help you unlock the "Happy End with Aiko" achievement.
(Good End 3 = Fun with Aiko)

You can watch it as a novel, or just fallow the order below:


01 - I know quite a bit about Basketball actually.
02 - Center.
03 - Double Dribble.
04 - Where you cover someone.
05 - Offer to help.
06 - Tell her about Rei.
07 - Not really.
08 - Hell with it, sure.
09 - Okay just a little.
10 - Check the indoor Pools.
11 - I'm broke.
12 - Take the Phone.
13 - Let's not drink anymore.
14 - Sandy Beach.
15 - I'll see about calling a repairman.
16 - Hell with it, sure.
17 - Not this time, sorry.
18 - Reception.
19 - Sandy Beach.
20 - There are no faults.
21 - Yeah.
22 - Seven.
23 - Truth.
24 - If you're sure.
25 - Sorry for the wait.
26 - Sorry I'm not in the mood.
27 - Sandy Beach.
28 - Topless.
29 - Aiko.

Aiko is a tricky one, as you come across the option for a trio in your relationship later in the game. But before that, you have to make sure to get Aiko's attention through sports. Giving correct answers give you extra points. The best way, is to go easy with her on the first option of intimacy, and let things advance. Deny all the other girls, especially Sakura. In the end play the topless game with her, and choose her as your only girlfriend.

This video will help you unlock the "Happy End with Rei" achievement.
(Good End 4 = Lovely end with Rei)

You can watch it as a novel, or just fallow the order below:


01 - I'm not big on sports.
02 - Let it go. / Offer to help.
03 - Tell her about Rei.
04 - Not really.
05 - Hell with it, sure.
06 - It's what Umi needs done.
07 - Check the Indoor Pools.
08 - I'm broke. / Sure Thing.
09 - Take the Phone.
10 - Let's not drink anymore.
11 - Swimming Pool.
12 - I'll see about calling a repairman.
13 - Yuuki may need help.
14 - Deflect.
15 - Hot Springs.
16 - (Optional location)
17 - Truth.
18 - I like you most.
19 - Sure.
20 - Sorry for the wait.
- (Save the game at this fase to reload and unlock 2 achievements later)
21 - Sorry I'm not in the mood.
22 - Swimming Pool.

By doing this playthrough, just remember to save near the end, as you'll have the opportunity to reload the game later and unlock 2 achievements really quick.
Rei is a tough cookie, she's suspicious of you, but as the days pass by she becomes more interesting, and it's actually a nice character. Just choose her for all your sentimental moments, and deny all of the other girls feelings. Do some work around the resort, and at the end when you meet Nymph just save your game, and keep playing till you choose to go to the Swimming Pool and Rei will be there with a nice proposal.

This video will help you unlock the "Dark Grave" and "Watery Grave" achievement in one simple row.
If you watched the previous video, where we get to be in a relationship with Rei, and you saved the game, this is how you reload and get the extra endings.
You can watch it as a novel, or just fallow the order below:


Dark Grave (Bad End 2 = Cheating dark reward)

Once in a relationship with Rei, you'll talk with Nymph, choose:
01 - Alright, let's do it.
02 - Tennis court / Sandy beach

Watery Grave (Bad End 3 = Cheating watery grave)

Once in a relationship with Rei, you'll talk with Nymph, choose:
01 - Alright, let's do it.
02 - Swimming pool.

Once the first achievement pop-in, just reload the game again and go for the second.
In the end what really matters is where you meet Rei.

This video will help you unlock the "Demon Slave" achievement.
(Odd till the End 1: Enslaved by a Demon)

You can watch it as a novel, or just fallow the order below:


01 - I'm not big on sports.
02 - (Optional choice).
03 - (Optional choice).
04 - Maybe a little.
05 - Hell with it, sure.
06 - (Optional choice).
07 - (Optional choice).
08 - (Optional choice).
09 - (Optional choice).
10 - Let's not drink anymore.
11 - (Optional choice).
12 - Sounds like your really need my help.
13 - (Optional choice).
14 - Ferris Wheel.
15 - I'd rather not.
16 - That sounds like a good idea...
17 - (Optional choice).
18 - (Optional choice).
19 - Alright, let's do it.

Even though most options are optional, you still have to show work done around the resort, that's why I kept scenes such as accepting help from Rei and others.
I also think it's a good idea to meet Minami once. Not a requirement, but... If Nymph is your Demon, surely Minami is your Guardian Angel, no doubt about that!
Just deny all the girls, except for work related activities, and be with Nymph 4 times. In the end you'll be enslaved by her.

This video will help you unlock the "Become a Merman" achievement.
(Odd till the End 2: Becoming a Merman)

You can watch it as a novel, or just fallow the order below:


01 - I'm not big on sports.
02 - Offer to Help.
03 - Don't tell her about Rei.
04 - Not Really.
05 - Hell with it, sure.
06 - It's what Umi needs done.
07 - Rocky Beach.
08 - Sure Thing.
09 - Hand over the bag.
10 - Take the phone.
11 - Let's not drink anymore.
12 - Swimming pool.
13 - I'll see about calling a repairman.
14 - Yuuki may need help.
15 - Deflect.
16 - Rocky Beach.
17 - Ferris Wheel.
18 - I'd rather not.
19 - Sorry, no.
20 - Lies.
21 - Sorry for the wait.
22 - Sorry i'm not in the mood.
23 - Swimming Pool.
24 - Minami.

Minami is by far my favorite option, but you have to visit Rocky Beach in every situation possible. Since I was to become a Merman I though being nice to all the girls was the correct thing to do. However, do not get involved with any of them. Just deny all her attempts for deeper relationships. Keep nice and professional. In the end, go for Minami and enjoy a deep sea love story!

This video will help you unlock the "Trio of Love" achievement.
(Odd till the End 4: Trio of Love)

You can watch it as a novel, or just fallow the order below:


01 - I'm interested in sports too.
02 - Offer to help.
03 - Tell her about Rei.
04 - Not really.
05 - Hell with it, sure.
06 - My Pleasure.
07 - Check the Indoor Pools.
08 - Sure Thing.
09 - Hand over bag.
10 - Take the Phone.
11 - Let's not drink anymore.
12 - Sandy Beach.
13 - I'll see about calling a repairman.
14 - Hell with it, sure.
15 - Lead the way.
16 - Hot Springs.
17 - Ferris Wheel.
18 - Sounds like a plan to me.
19 - (Optional choice)
20 - If' you're sure.
21 - Sorry for wait.
22 - Sorry I'm not in the mood.
23 - Swimming Pool.
24 - Aiko.

Getting the Trion of Love achievement consists in having an affair with 2 girls and make that a serious decision. Deny all girl's affection expect Sakura and Aiko. Aiko will always have more attention. Aiko goes for the feelings and Sakura for everything else. This time around you don't need to get Aiko's attention for sports, and choosing her at the end gives you a nice finale!

Even though I played the game for myself, and completed all the scenes, I have consulted Kimchi Tea's Guide. It's great, but in some cases I followed a different path because I felt it made more sense to the story. But Credits go to him, as he did a deeper guide showing all the 19 alternative endings.
Worth checking out!