I tried this game twice, maybe two years apart. My main issue with it was that the core combat is very, very boring. You swing your sword. That's basically it, at least for the 6 hours I put into my second save file. You also don't get any damage upgrades so each enemy is a chore to kill, making later parts of the game feel awfully sluggish. Games like Hollow Knight also have a sword, but give you spells and different moves to spice things up while having more interesting enemies to fight that get easier once you find damage upgrades. Haiku lacks those features.
The graphics are nice, the concept is cool, and I can tell a good amount of effort went into this game, but the combat is a fatal flaw in my opinion.

Would recommend as baby's first metroidvenia.
It has a lot of heart but nothing to really write home about, i would buy it if you need a small, fun, cozy, easygoing game to kill a afternoon or two.

6/10

fun little metroidvania, pretty easy tho