Kotarou Puppy's Car Dilemma (Patreon)

Reward for Maki 

(Who commissioned this pic to be full-colored) 

Poor puppy girl, Kotarou couldn't reach home in time, after overeating at the local festival, and makes quite the stinky boomboom on the ride home and....

Well you can actually read the whole story here on OmoOrg:

 https://www.omorashi.org/blogs/entry/1458-chapter-5-wanko-festival/