So the baby is the black haired guy and not the blond haired guy right ?

Yup :-) :-) :-)

Yep. The Omega never slept with the Alpha. We learned that in Chapter 5.

There was intercourse between the two, they just didnt conceive.

Penetration...for a little bit, but it stopped pretty quick.

Nope, it was the full thing, you can see Kei laying on the bed all wet and stuff, in chapter 5 when ekihito says 'nothing happened in the end and you were even screaming it" he's referring to the fact that kei didn't get pregnant... that was what kei was screaming about while ekihito raped him