Unknown bites

Hi! I wanted to come on here and see if anyone has ever had this happen before. My bf has been getting more and more little red spots on his legs. (What we assume to be bites) but i literally have none. We share the same bed, and everything. Havent found any bugs that we think could be the problem. I know we sometimes get ants and little house spiders but haven’t found any evidence. Its just so mind boggling to me that it is ONLY him. I haven’t even got one bite. Am i just not this little buggers preference??