James: When you're upset James will take you to his room or the couch in the common room to cuddle. He'll play with your hair and let you talk about what's bothering you. If you don't want to talk then he'll whisper sweet nothings in your ear until you calm down.
Sirius: Sirius always wants to make you laugh. That's no exception for when you're upset. He'll try his hardest to make you smile, the easiest way is to compliment you like you're the only girl in the world. If you're really upset and get annoyed with him trying to make you smile then he'll hug you for a really long time and tell you everything is going to be okay.
Remus: You love to hear Remus read, but he doesn't like reading out loud. When you're upset he'll find your favorite book and start reading to you. You'll lay with your head on his chest as he reads and listen to his voice and heartbeat. Eventually those sounds calm you down and you're eventually able to talk about what's bothering you.
Severus: When you're upset Severus will take you to his room and lay with you. Your legs would be entwined together and your head would be on his chest. He would help you calm your breathing and hold you as long as you need.
Regulus: When you're upset Regulus sits with you in front of the fire in the common room. He'll lay a blanket over the two of you while you rest your head on his shoulder. You'd eventually fall asleep and he'd lay with you until morning.
A/N: It's really hard for me to write for Snape but I'll try my best so I'm sorry if it's bad.
