Yep, David nearly blew the masquerade (indirectly) and shot a guy over a girl he barely knew and could've been there to kill him.*
Granted they probably fixed the 'barely knew' part. As soon as Sabrina got over the whole 'he shot someone' part.
Dulcinea effect, lel.
Yuri would be fairly likely to be at least civil to everyone, even if Kiri tried to piss him off on purpose. He likely talks a lot with Jana, Trude, Sabrina and Larissa. Also Wiles
because Batman and Alfred.
Sabrina would probably still only know Corentine, Wiles, David and Yuri, given the whole Monster Hunter thing and probably suspects anyone else is trying to befriend her because they're scared of her.