Weird comic from my childhood (please help me find it!)

I remember reading it all the time in the school library, although im pretty sure it isnt there anymore. So im seeking the help of the internet

It was a comic, telling the tale of two boys, probably brothers, who in the intro find out the closet in their parents bedroom has a hole which connects it to their sons bedroom? creepy

It had a sort of invader zim artstyle, with a lot of grotesque character design and detail, with stylized heads and bodies, but probably not 1 to 1 with invader zim.

Then some stuff happens and the brothers end up in a dark & gloomy forest, with a painting of the mona lisa (or some other renissance painting) in the middle of nowhere. turns out behind it was a girl, who thinks the lady on the painting is her mother (???)

sorry for the unexplained connecting pieces, i really dont know how one event led to another lol

Then they somehow get on a boat, with a pirate just muking about on it. they then are confronted by a giant kaiju like monster, and the girl turns into a kaiju monster and battles the beast, but she is (probably) defeated, and the brothers are eaten by the monster, ending up inside a city which is inside the monsters stomach.

They eventualy get to the town square (i guess) and mess with something which ends up killing the monster, washing up ashore on another monster city.

After that they somehow end up with the girl again. then they come back to their house and a robot is trying to kill the, somehow related to how they were transported to the forest and back to their house. theres also ajoke about a pineapple which one of the boys have. i guess.

Thats all i can remember, if anyone has any idea about what i rambled about, please leave a comment :]