The One Who Smelled It

You cast this spell to in an area up to 5 square feet letting off a small smell (of caster's chose) that last up to 30 seconds. If the target fails at the saving throw (WIS), aka: mentioning the smell, a strong odor as well as farting sound will follow them for the next minute, giving them disadvantage on charisma (CHA) rolls. (If the target rolls a natural one, they will have bowel movement in their pants. If they roll a natural 20 the negative effects will backfire and effect the caster.)

If there are multiple targets in the area, the one with the lowest roll gets the effects.