I have goldfish memory

hiii I've read a manga before that I really like but forgot the title!! it was something bout a little kid i think? I don't remember if it was isekai since it's been so long since I last read it. anyway he's of noble blood then ones day, this beast man accidentally bit him I think? then an agreement sort of showed up and uhhhhh... anyway if anyone knows the title, please do tell me!!