If you don't mind freakiness, MADK by Ryo Suzuri was pretty memorable for me.
The art was gorgeous, the character designs and world was pretty interesting.
God, the hatching on the facial expressions and use of negative space to manipulate the atmosphere of the scenes was super inspiring.
Reading it felt like I was willingly trudging through sticky tar with great delight despite my skin slowly burning from the tar's absorption of heat.
The main character turns from a miserable shut-in, to a sadistic yet 'pure'(I think sincere may fit more, but this also feels accurate to me) demon of a character.

Anyone got good SAD and ANGSTY unrequited love bls . Ongoing or completed