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.
Isaac and the Kaylon generally are very good. Even Charly admitted that
spoiler
killing the builders was entirely justified and she was specifically there to be the Dr. Pulaski to Isaac's Data.
Speaking of which, what did you think of Charly? I've seen that the fandom's reaction to her is generally very negative, and I think it's because as a younger, hotter Pulaski she gets the hate Pulaski did but magnified by the Gamergate lens.
I thought Charly was a very cool character overall.
spoiler
I liked her time travel adventure with Isaac especially.
As a weird coincidence, she looked almost exactly as I mentally visualized the first main protagonist from my novel trilogy, and had some personality quirks to match,
spoiler
except of course my character used her machine affinity with sympathy with machines and a bit of a mild contempt for other human beings after the hard life she had been through as a post-American-empire-collapse refugee.