Sauce seems to be "Fight Ippatsu! Jūden-chan!!"

Tried a couple of image search engines (Google, SauceNAO, WAIT: What Anime Is This?) earlier today and came up with nothing. Then I remembered TinEye exists and tried that. Bam. Instantly found a gif with the name of the anime in it.

Some google searches showed some, uh... unusual stuff though, so be forewarned to any other random individual who's curious about this.

𝑴𝒖𝒔𝒕. 𝑭𝒊𝒏𝒅. 𝑺𝒂𝒖𝒄𝒆.

Must. Find. Sauce. (In case Steam can't actually display these unicode characters or w/e.

+rep very good time i had

I wish I could tell you. I found it in a large collection of GIFs and forgot to note the source anime.