I really need to not let myself try to play for maps like this while I'm feeling tired. Well, more on the tired tired side, not just "my eyes feel a little heavy/hurt a little" tired. I can play fine on the latter (I feel a bit of that as I upload this), but the former is not good to play on. Just a PSA.
Osu! is a rhythm game based off of Osu! Tatakae! Ouendan! and the American release Elite Beat Agents. In these games you click circles to the rhythm of the song. Osu! also has different rankings you can shoot for, with SS being the best (Hit every note and have 100% accuracy). There are also mods like Hard Rock, Hidden, Flashlight, and Double Time/Nightcore if you want to increase the difficulty even more.
There are 3,996 views in 788 videos for osu!. His channel published over 1 day worth of content for the game, roughly 20.07% of osu! content that JonathanScarlet has uploaded to YouTube.