When Kevin absorbs something, does is cover him (like armor) or does he become it?
It covers him, but he also gains strength from it.
>If it covers him, does Kevin have any problems lifting himself or breathing?
In the episode "Kevin's Big Score", did Kevin become the diamond or get covered in it? If he got covered in it, he sure has a lot of strength.
It covered him.
Did Kevin's powers evolve (like from draining energy to absorbing materials) or is he just using it in another way? And can he still drain energy?
No his powers are the same, he's just using it on solids instead of with energy. He can still absorb energy.
Does Kevin have alien ancestry or is he really a freak?
We haven't said.
He could've thought he was a freak like how Gwen thought her powers were magic.
That's not a question.
Why do many characters in Alien Force have something to do with energy or aliens? Like Mike Morningstar, Gwen, Brainstorm, Chromastone, Kevin (if he still has those powers) and others.
The name of the show is "Alien Force," hence the large number of aliens. We also use force a lot. Without energy, nothing can happen.
Why is it when Mike Morningstar absorbs girls "life energy", it's yellow but if Gwen uses mana (life energy), it's pink. Did Mike convert it into something else or what?
No, he didn't convert it, he absorbed what he can use. Life energy is a subset of manna.