why japanese mangaka always try to make a human adscended to godhood.

Why should I believe in ANY such fictional things, especially one with such a poorly constructed narrative as allah?So you think there are any god beside allah?
Yes, Fiction.Fiction ?
Humans can ascend to godhood, if some god wills it. Because by definition, gods are omnipotent and almighty. Omnipotent means, that they can make a person into a god.we human cant adscended to godhood or what god,gods,anything.
Japanese "kami" are a bit different thing and in essence they're closer to shamanistic(?) spirits. There are definitely nigh-omnipotent or fully omnipotent Kami (Amaterasu, perhaps?), but aside from those they're weaker than mythical beings from other religions and have limited influence. Also, in Shinto a human can become kami.at the same time Japan is also known for turning anything to gods