Middle finger and Group hug for any!
I’m probably going to do this for all of my platonic f/os and my relationship with them in general! (so Pidge, Alfred, Margu, Tintin and Haddock)
Middlefinger: We’ll definitely fight every now and then (it can’t really be avoided) but we solve it by leaving each other alone for a while to be angry, then when we’re ready we talk it out. I don’t think I’ve ever fought with Margu (she’s a little kid after all), and Tintin and Pidge are pretty good at conflict resolution, as are Al and Haddock but they need a lot of time to let the anger run it’s course.
Group Hug: It depends, as all of the platonic f/os save for Alfred are long distance friendships/family ties, so Matthew really only sees them when he tags along with me on visits (as well as calls and video chats).