Hello there! I definitely think Adam would be the type to love, or at the very least find it amusing if a PC loves to bite him.

For playful biting, he just lets it happen while laughing because he would find the habit adorable. Same for affectionate biting.

For angry biting, I assume that the situation is genuinely hostile? I imagine that Adam wouldn't be his usual self during these moments because he would also be genuinely pissed, so he would try to push PC's head away by grabbing them by the hair and redirecting their face to a different surface. Would probably comment on needing to "muzzle you like a damn mutt."

For bratty biting, he would still find this amusing, but he would retaliate and bite PC back. I think he would also playfully dodge and then lunge to be the one to bite PC first or harder. This is done while he himself isn't angry and he sees the situation as lighthearted or unserious, hehe...

During sex... He would like it because you're asserting yourself in your own way! He wears very conservative clothing, so he wouldn't care if you leave marks on him. And if you have bite marks on you from other people (bonus if Eden), he would bite down on them too to overwrite the marks and make them his.