Dramatical Murder! It’s a BL game made by Nitro+Chiral who are known for their Dating/BL games (and notorious for their bad endings!)
It’s basically about this dude:
Our cutie Patootie protag Aoba, and his involvement in a lot of strange goings on in his hometown!
It’s set in a futuristic setting on a group of islands. Basically this company has taken over part of the island, and a lot of weird shit is going on. Lots of gang activity, and based upon who you chose to go after you’ll face different plot twists!
It is a 18+ game! Just remember! It’s very good though, and I hightly recommend playing if you like the genre!
It’s for PC, but you can get it on a Mac! There are some guide videos on youtube on how to download!