[Dayton of Abyss]

Sans decided he may aleviate that rule . . . either when he knows Papyrus really won't do that sorta stunt again, or when he's older, whichever comes first. While Sans didn't want to do this, even after hearing his brother's apologies, so he just focuses on what Papyrus did and the bad that could come from it, and began the punishment.

"It's too late for that now Papyrus" he simply answered, hooking one finger under the waistband of Papyruses pants and underwear, and quickly pulling them down to show his bare backside, and then put an arm over the small of his back and started spanking. Raising his hand high, Sans then crashed it down on the middle of little Paps rear end, and then gave him spanks to each cheek left to right and right to left, with little pause in-between spanks administered to poor Paps bottom.