Technically, when ML asked MC if he wanted to shower, that was offering aftercare. And depending on how he did it, it was done in the shower, whereas he would've washed MC's body and made sure there're no rips or tears. This was probably the case and instead of drawing the scenes, the Author condensed the scene and had the readers to assume it. OR like @Tan_Coco said, ML was going to do aftercare, but MC fell asleep. In most cases like that, the Seme (or Dom) should and or would go on ahead and provide aftercare while Uke (Sub) is asleep.
It didn't seem like aftercare if you pass out and sleep in your own crap. After you wake up you can always wash yourself. The point of after care is so you sleep in your own "sh*t". But to each their own.
If they had both fallen asleep then sure. But wyd did ChiYoung look all clean while the puppy had "sh*t" all over him?!?
No aftercare?!?! Shame on you wolf man