Face claim
When two people get all over each other like they're trying to stick to each other with glue. It's like claiming someone with a hickey, but higher up and more messy.
They were face claiming in the hallway like they were trying to melt into each other.
He face claimed her in the middle of the pizza shop, and now they're both covered in cheese.
They face claimed in front of the whole class like they were trying to prove who was more embarrassing.