Here is the full list of all 31 Guilty Summer Kiss 2 - there are Bloody Secret achievements.
Put 100 likes to Hisano in underwear
Put 100 likes to Miya in underwear
Put 100 likes to Lisa in underwear
Get into someone else's body
Become responsible for Miya's reclamation
Show Lisa the photo of Arisu
See the fight of Nakahara sisters
Betray Arisu
Not to step on the shoelace when running away from Miya
Agree to help Hisano for money
Hug Lisa
Kiss Lisa
Be killed by Rei
See Lisa betraing her mother
Prefer Lisa to Miya
Listen to Lisa singing
To mix up Lisa and Miya
Have a successful date with Lisa
Say "No" to Rei
Let Rei live in your house
Find Arisu
Be saved by Miko
Talk to Miko all night long
Not to go with Miya to the lab
Find out what heterochromy is
Be called boring
Find a new body for Hisano
Die for Rei's sake
Be seduced by the headmistress
Tell Miya you love her
Prefer Miya to Lisa