Only 28/32 achievements are currently obtainable, the other 4 are in inaccessible routes due to coding errors. I made a thread in forums (click here) about it, but don't expect developer to fix them, they don't seem to care at all about it.

᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁・♡・᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁

✦ Start a new game
✦ Offices
✧ Praise her multitasking skills.
✧ Try to find a common interest.
✧ Invite her to the science club.
✧ Okay.
✧ Two chemicals mix together, right?
✧ Newton's inertia, right?
✦ Save 1
✦ Classrooms
✧ Rinnie.
✧ Compliment her fashion sense.
✧ Ask if she likes sports.
✧ Invite her to lunch.
✧ No need.
✦ Save 2
✦ Track Field
✧ Ask if she's doing her homework.
✧ Ask about her favorite food.
✧ Lie: vanilla pudding.
✧ Offer to treat her to something sweet.
✧ Go to the office.
✧ Yes.
✧ Search Bri's desk.
✦ Save 3
✦ The Pool
✧ Look around the poolside.
✧ Ask what she plans to do next.
✧ Flirt her up.
✦ Save 4
✦ Offices
✧ Talk about lunch.
✧ Remain silent.
✧ Joke around with her.

Charismatic

Successfully seduced Bri.

✧ Any choice.
✦ Save 5
✦ Leave
✧ Talk to them.
✧ Make small-talk.
✧ Ignore Cheryl.
✦ Save 6
✧ Ask Luci to spend time with you.

Taming the Fire

Successfully seduced Luci.

Incubus

Became strong enough to transform into an incubus.

᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁・♡・᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁

✦ Load Save 6
✧ Ask to do something all together.

Slave

Became Akame's eternal slave.

᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁・♡・᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁

✦ Load Save 2
✦ Pool
✧ Luci.

Locker Room Lover

Snuck into the locker room.

✧ Check around the area.
✧ Focus on Cheryl.
✦ Science Lab
✧ Tap her on the shoulder.
✧ Offer to help her.
✧ Do her chemistry homework for her.
✦ Corridor
✧ Chit-chat with her.
✧ Grab some snacks with her.
✧ Continue chatting.
✦ Leave
✦ Save 7
✧ Choose Cheryl.

Riding Wild

Successfully seduced Cheryl.

Game Over

Failed to please Akame.

᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁・♡・᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁

✦ Load Save 7
✧ Choose Luci.

Luci's Ending

Obtained Luci's romantic ending.

᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁・♡・᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁

✦ Load Save 3
✦ Corridor
✧ Roast the guy.
✧ Chat all the way there.
✧ Ask about the science club.
✧ How about tonight?
✦ Offices
✧ Talk about lunch.
✧ Remain silent.
✧ Joke around with her.
✧ Any choice.
✦ Classrooms
✧ Join a club.
✧ Something physical and proactive.
✧ Swimming club.

Swimming Club

Joined the swimming club.

Bri's Ending

Obtained Bri's romantic ending.

᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁・♡・᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁

✦ Load Save 4
✦ Rooftop
✧ Comfort her.
✦ Classrooms.
✧ Join a club.
✧ Something physical and proactive.
✧ Sports club.

Sports Club

Joined the sports club.

Rinnie's Ending

Obtained Rinnie's romantic ending.

᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁・♡・᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁

✦ Load Save 1
✦ Classrooms
✧ Rinnie.
✧ Ask her to tutor you.
✧ Talk about the game.
✧ Ask for her phone number.

Creepy

Asked for Rinnie's phone number despite being strangers.

✧ Sure. It wouldn't hurt.
✧ Something physical and proactive.
✧ Pottery club.

Pottery Club

Joined the pottery club.

✦ Rooftop

Pointless

Wasted your after school time going to a club meeting.

✦ Quit this playthrough.

᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁・♡・᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁

✦ Load Save 1
✦ Offices
✧ Just go in.

Caught Red-handed

You were caught snooping by a teacher.

✧ Sure. It wouldn't hurt.
✧ Something mentally stimulating.
✧ Literature club.

Literature Club

Joined the literature club.

✦ Quit this playthrough.

᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁・♡・᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁

✦ Load Save 1
✦ Offices
✧ Peek inside.
✧ Check her computer.
✧ Yes.
✧ Look in her desk.
✧ Yes.
✧ Check her papers.
✧ No need.

Detention

Faithfully served your sentence.

᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁・♡・᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁

✦ Save 8
✧ Go to the office.
✧ Yes.
✧ Search Bri's desk.

Twice the Trouble

Get two detentions in a row.

✦ Offices
✧ Give up.
✦ Offices

Bri's Stones

Returned Bri's strange stones.

✦ Quit this playthrough.

᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁・♡・᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁

✦ Load Save 1
✦ Track Field
✧ Buy her something sweet.
✧ Invite her to a game later today.
✧ Cookies
✧ Calm them both down.
✦ Track Field
✧ Talk about Cheryl.
✧ Sure.
✧ Search for Luci outside.

The Right Choice?

Chose Luci over her sister.

᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁・♡・᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁

✦ Start a new game
✦ Offices
✧ Praise her multitasking skills.
✧ Try to find a common interest.
✧ Invite her to the science club.
✧ How about tomorrow instead?
✦ Track Field
✧ Buy her something sweet.
✧ Invite her to a game later today.
✦ Save 9
✧ Go on a date with Luci.
✧ Lie.
✧ Something salty and a drink.
✧ Calm them both down.

Slick as Sand

Completely messed up your date with Luci.

᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁・♡・᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁

✦ Load Save 9
✧ Go on a date with Bri.
✧ Lie.
✧ Don't they use batteries?
✧ Isn't that a song?

Rudimentary

Couldn't correctly answer even one of Bri's questions.

᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁・♡・᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁

✦ Start a new game
✦ The Pool.
✧ Rinnie's.
✦ The Pool.
✧ Check the corner.
✧ Sure. It wouldn't hurt.
✧ Something mentally stimulating.
✧ Science club.

Science Club

Joined the science club.

✦ The Pool.
✧ Check the poolside.
✦ The Pool.
✧ Flirt her up.
✦ The Pool.
✦ Leave

Normal Life

Returned to your normal, everyday life.

᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁・♡・᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁

✦ Start a new game
✦ Rooftop
✦ Rooftop
✧ Ask about her meal.
✧ Tell her about a science experiment.
✧ Try to get her phone number.
✧ Sure. It wouldn't hurt.
✧ Something mentally stimulating.
✦ Save 10
✧ History club.

History Club

Joined the history club.

✦ Rooftop

Persistent

You just can't seem to give up on the impossible.

᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁・♡・᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁

✦ Load Save 10
✧ Film club.

Film Club

Joined the film club.

᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁・♡・᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁᠁