You were on a mission with Snape, your enemy and colleague. You two ended up in his old girl best friends house and had to stay the night there. She was very rude to you but Snape did nothing. It was raining outside and she left you there, she knew you were out there but did nothing until Snape noticed and brought you in

"How long have you been outside for!?"

He got his cloak and covered you up, he genuinely looked worried for once