Theta Pepper
Met Tynan through Eta Pepper, her youngest sister in Hufflepuff (NPC), and Tim Pepper, her cousin in Ravenclaw (NPC), who are 1st years who introduced him out of politeness before an Astronomy lesson late on a Wednesday night. Theta had been up in the tower running through a few points on an essay with Professor Trishna before the first years had their lesson, and bumped into them.

Thinks Tynan is great and admires the way he doesn't let his facial disfiguration get in the way. Theta goes out of her way not to stare, and later went out of her way to introduce Tynan to Ambrose. Acquaintances, but option to know each other better.

Ambrose Pepper

Introduced by Theta in October last year because she figured they'd have things in common given Ambrose's interest in CoMC. They knew of each other anyway, but Ambrose had been a bit awkward to talk to Tynan because Tim had accused him of staring at Tynan in the first few weeks of term in September. They're in the same house together, I figure they'd hit off well, because they both like being outside, Tynan really wants to do CoMC and Ambrose is now really enthusiastic about it, and they both have academic difficulties - Tynan's more writing, Ambrose more spellcasting, but equally irritated by the fact they have to do it to get anywhere. Also, they're boys.

Francis Pepper

Has heard of Tynan from Ambrose and Tim's letters, though hasn't met him. But if he's about at the careers fair, he'd hope someone would introduce him, as he's a friend of the family.

Updated!

Sorry if I'm doing it wrong; didn't see a code for you.

Anyway, I think Peter and Tynan have probably not interacted much unless Tynan initiated it; Peter would have a very hard time looking him in the face without blatantly staring at the scar. Not to mention, Tynan's sullen attitude and roughness would be very off-putting. Don't know how Tynan would react, but Peter most likely avoids Tynan.