I'll start off by listing mine:
The T-800, Terminator 2: "I know now why you cry, but it's something that I can never do." Gets me every damn time.
ADA, Zone of the Enders: I think I'm the only one who played this game more than the MGS2 demo that came with it. I will never not laugh at the exchange of "You may speak like a human, but you're still a heartless computer, aren't you?" "That is correct. What is the problem?"
Codsworth, Fallout 4: He survives the nuclear holocaust despite not having a bunker and waits 200 years for you to come back. When you look at what changes his relationship with you, he mostly just wants you to be nice to people. I never swapped him out as my companion.
B.O.Y.D., Ducktales 2017: He's adorable. 'nuff said.
Bishop from Aliens.
Bishop is my favorite by far. He's such a great juxtaposition to Ash from Alien. He serves as proof that the technology itself isn't evil, but it can be if its only purpose is to serve capitalist interests.
For real. Also I love how Lance Henriksson portrays the facial emotions. Such a great character.
Extremely underrated performance.
tbh I love Ash too, in a different way. All the Weyland-Yutani androids are tragic. They're all slaves, down to their core, and they seem aware of it. Every one of them is played with a sort of morose serenity, like they're compelled to do every movement they perform against their wishes.