KAMIKO

Simple game. Simple to learn. Simple artwork. Simple choice of character colours. Simple lore. Simple to understand controls. Simply beautiful music.
Simplest decision to instantly buy this game.

Editing a previous non-recommendation since I fixed my issue. You should be aware going in that the game is frame-rate sensitive and most people who have had problems fixed them by lowering the frame-rate of their monitor. That didn't work for me since I was already at the lower frame-rate, but I'm not sure what finally fixed it... I did try various compatibility modes and running as administrator but didn't think those made any difference initially. Still not sure what made it decide to play nice, but segments of the game are impossible due to movement issues if it isn't running correctly.
The game says I've played 5 hours, but the first almost-two of that was me getting to the second level within 10-15 minutes and encountering the first impossible segment. Since all of the documented fixes and online advice weren't working, I put in for a refund and had almost written it off, but decided to mess around a little bit more since launching the game to test fixes would only add a few minutes to my time and keep me under the two-hour refund limit. Lo and behold, the game did eventually work properly and I cancelled the refund request. Just want to get the context out there so you know how long it actually takes to play.
It's a fun enough game, short and the bosses are fun to learn. Some segments of the game were frustrating until I learned to cheese the enemy spawning system. I got the game on sale for just over $2 and would call it worth, but I'm not sure I would have paid more than that. I'm sure completion times vary and I do play a lot of games like this, so maybe my playtime is on the low end? But I can't call it a particularly challenging game and I think it's safe to say it's only 3-5 hours to 100% the game.

KAMIKO is a very simple game that doesn't do anything outstanding but still manages to be great.
The visuals are very appealing and easily the thing I like most about this game, but the music is good too, and the gameplay is simple but effective and clean.
I haven't finished it yet, but it's a fun little game made with love.
If you got a few bucks to spare, definitely get this. It's the equivalent to most people's daily coffee.