Please help! I am so confused.... he wants to take it slow.. Guys or Girls please help!?

I'm sticking with the gay theory. But before you said he had been single for 15 years and now you are just saying 8, to make it seem better than it is. 15 years is a long time to not have a girlfriend. My brother is the geekiest surgeon you will ever meet... socially incompetent mild mannered kind of guy... and even he finds girlfriends. Red flags!