I almost forgot that this thread exists.
Anyway, I have been taking care of my friend's pet hamster called Choco for a few days now, and she gets along very well with Felix surprisingly.
Felix have been so fixated on Choco to the point where he stays by Choco's side almost 24/7. It's great that Felix has taken an interest in her, since I sometimes feel sorry that I don't always allow him to venture outside.