[@Letter Bee]

If you're asking, I'll honestly answer, haha.

Absorbing only as much extra energy as his body weight would imply that the essence of magic can be quantified by units of measurement usually reserved for physical bodies. I don't know the laws of this world, so it could happen, but I think you'd have an easier time RPing if you didn't have to ask about the "amount of magic used in kg" for every spell Mikhail drains.

Nothing else warrants concern, at least, to me.

Of course, this is just a cursory opinion. Cool character, though!