want to know if this sounds like a cool plot starting point

I think you should postpone the "chance encounter" thing. Or erase it completely. Find another way to introduce the heroine. The "chance encounter" trope is too cliché

 

ok noted, i might make it more along the line of him helping her from some humans because of his biasness towards humans.

but he has to meet her early because the first arc is about the rebellion and him choosing to help her for various reasons such as he could gain the backing of the elfs so he can grow faster like the heroes who are backed by the human kingdom, he needs information on the world and its faster to talk to people than read books, not to mention because of his hate fro humans he sees it as a way to stick it to them and get a laugh, along with a few other reasons

 

But why does he help her?

 

It sounds too generic. Make your protagonist more insane and psychotic and it'll give him some personality. It's not fun when they are good but misunderstood (an awful trope imo). Also don't make things black and white. What if the demon king secretly is lying and he's the goddesses brother and there's three siblings who are constantly fighting. You need to make things more interesting

 

Why don't you try using unique creatures that first starts out weak then with gradually gets stronger and sronger ? This is just my opinion but I like the concept of summons get stonger with the protagonist. Probably this is just me being biased from reading Ark.

 

I really can't imagine a normal student getting psychotic and insane because he had to face starvation... Atleast his mind would return to normal as soon as he eats regularly again? ... (half joking here)
To get away with a psychotic and insance MC, he either has to be like that from the start or you have to slaughter his whole family and friends IMO...
Humans don't just randomly lose their mind and go on a rampage ^^

 

well I imagine that they can't overthrow the demon lord in only a few days. Imagine starving alone, unable to move for a couple years. Anyone would go insane from that

 

You got a point there... But I still think that is something that should fix itself over time... (I'm probably the only one that likes the character development in arifureta... I think it is quite "realistic" and to be expected from a normal human being)

 

Come on, I want a real anti-hero, someone like Thomas Covenant, not the stupid self-righteous arrogant a-holes in most xianxia

 

that idea is quite appealing... approved

btt:
@Esperreal could you explain your fighting system in more detail.. I don't want to recommend some skill without knowing in what kind of environment it should be considered "above average but not extremely OP"...

PS:
@Arcturus I recommend you Meow Meow Meow. After reading your signature I guess you will like it

 

As a caveat to what I said, he could do some terrible things, but eventually feel some remorse and try to find some way to assuage his guilt. He doesn't have to stay completely psychotic, but if you do this you need him to stay at least a little crazy.

The straight psychotic anti-hero route also works, but it's harder to make that kind of character likeable. For a good example, read Mark Lawrence's Prince of Thorns

 

@Esperreal
Hmmm... How about magic?

But instead of normal magic- he can only absorb instead of create, e.g. He can't create flames- but he can absorb the heat from someone, sort of freezing them; or he can't make a shield- but he can absorb kinetic energy, making moving things stop.

His magic would seem like water/ice magic- but it's not. He can't make ice arrows or similar constructs- but he can freeze people by absorbing heat. They don't turn to ice- they just turn cold- so his magic would be cold magic?

He can absorb light- so he can turn shadowy? He can absorb gravity- so he can make his enemies fly off then fall?

It sort of ties in with being trapped in the void space- which is why his powers are void related.