Frisk.

Frisk is the 8th Human to fall. Chara is the 1st, and the only human to be seen alongside Asriel. The human in this comic is definitely Chara, as they are the human who commits suicide via Buttercup.

90% of fan comics have frisk along with Asriel, because everyone likes to picture a world with asriel back. Chara has a very specific look about their face.

Chara has the one strip that's in the center of the jumper whereas Frisk has two.
The comic shows the human only having one. Its Chara.

both frisk and chara have four strikes. Chara's is green yellow green yellow with black pants, and frisk's is blue pink blue pink with blue pants

Sprite comparison.

Except that's wrong. Chara has 1 yellow stripe, with a green shirt, and Frisk has 2 pink stripes.

Secondly, if you go to their Tumblr, it shows how they draw Frisk and Chara, pic related. Frisk has squint eyes, Chara has open eyes, and only 1 stripe, as in the canon sprite.

The comic is Chara, not Frisk.

Don't know why I bother with you, to be honest.

this comic's called Dreemur reborn, so titled because it's an AU where Asriel remains a goatkid when you beat him.

But it isn't: hotlegmeme.tumblr.com/post/135867734628/felt-like-drawing-the-demon-child

Dreamer Reborn's Tumblr is here: dreemurr-reborn.tumblr.com/