Play Friday Night Funkin FT. Sans online free at fnf.gosprunki.net. This FNF mod (original by @cabalex, current version v25v4) takes Boyfriend and Girlfriend into a mysterious alley. They discover a door with fire underneath, leading to a strange bar filled with funny monsters – including the infamous, lazy skeleton Sans from Undertale.
Sans challenges Boyfriend to a rap battle to decide who closes the bill for tonight. Use WASD or arrow keys (configurable in the options menu) to hit the notes. As the manual says: “It's basically like DDR, press arrow when arrow over other arrow. And uhhh don't die.”
For best performance, use the Turbowarp link: https://turbowarp.org/738290373. Want to create your own FNF mods? Check the modding guide: https://cabalex.github.io/fnf-song-converter/guide/.