Johanna and ainet will be friends since they're twinsies. They're both on sentry and in medical. Johanna's also the patient, calm in a crisis kind. She's seen more warfare than she cares to count, so she knows how to keep a cool head. ...you know all about Johanna obviously.
She probably will be friends with Amelia too. Johanna's an extremely easy person to befriend. She will embrace anyone so long as they're not malicious or evil. Seriously.
Alec goes to the school, and is prone to injury, and just spent two days in the infirmary because he passed out after coming back from 1925 so he likely met, saw, spoke to Ainet. And was probably a dick because he lost his emotions following passing out. Sorry, Ainet. But he's usually nice to the medical staff since he needs them so often. He's probably on a first name basis with all of them at this point.
He doesn't give much of an extensive shit about Amelia but he agrees with the sentiment, she's pretty fucking hot. And he'd tap that.