Need help find a psychological yaoi or shounen ai

Okay here is what I remember about it. It’s a pretty long manga. Okay basically the main character starts out as he has lost his memory and his best friend is a there to help him out. The main character lives in his best friends house who is supposedly a only son from a rich family and they had been childhood friends. Well anyway spoiler but the best friend is actually pretending to be the main character and have the main character be him because the best friend love the main character but the main character pretty much played with his best friends emotions and feeling since he was young. The best friend pretty much just wants revenge in a way by putting the main character through everything he went through. They become sex friends at one point and I remember there was one big part to it being the main character catching (Originally being the best friend but because of the lol game he is playing you don’t know that till near the end) his best friend having sex with a maid because “their just playing around” or something like that. Well anyway near the end you find out that the main character losing his memory’s and his fight to get them back has been an ongoing process because the main character is a scientist (I think) and he pretty much finds a way to control a persons mind by making the forget stuff or a drug he uses I’m not a 100% sure. Also either the servants are a part of the main characters lil brain washing drug or their robots either way in the begging the main character kinda makes a friend with a pink haired maid and at some point he realizes that her memory resets I think every day along with the others. I also know they live out in the middle of no where with it snowing a lot (or it was just harsh winters) anyway that’s all the big details I remember about it. I’m sorry if it’s confusing it’s confusing to me.