That shape and that position would be perfect for a paludarium.
That is a tank where plants grow up out of the water.
If you chose plants like pothos or peace lily that have low light requirements, then a north facing window wouldn’t be a problem.
It would look stunning growing up in that position. Absolutely stunning.
Here are a couple of pics to show the potential
: mature setup; betta, purple rasboras, male guppies, amano and wood shrimp. Heavily planted.
22litre cube tank
: (Tagawa); betta, yellow dwarf shrimp. Pond snails and 1 assassin. Heavily planted.
Midnight in the 57litre tank
(Midnight) ember tetras, 1 amano, 1 ghost, 1 nerite, pond snails, 1 assassin, doing his thing. Heavily planted.
; honey gourami, cherry barbs, green neons, otocinclus, nerites, pond snails, amano. Heavily planted.