Resized to 53% of original (view original)
Artist's commentary
Skeb commission!😑🐟💦
Source: https://twitter.com/noaharbre/status/1994442471489651022
Adult Frisk and Undyne from Undertale having sex. Frisk is licking Undyne's foot. Undyne's armpits are showing. Both of them are naked.
The pose is like this:
https://files.catbox.moe/h0xe8i.jpg
https://freeimage.host/i/FObizut (back up link)