You know those moments when you're really thirsty and just grab the first thing in the fridge, only to take a big gulp and empty the bottle in one drink? Doesn't matter what was in there, it just needs to satisfy your thirst?
Suigetsu had those moments quite often, getting dehydrated rather quickly. So he had gotten quite the few scoldings from his teammates. Not that they ever bothered him. It never stopped him from doing it again and again and again. Suigetsu did prefer water, but the others tend to drink something else and he would just make use of that.
You can imagine what his face looked like when he read the note that was scribbled on the bottle, after he had emptied it of course.
Don't drink this! Collecting spit samples from people. That means you, Suigetsu! Stay away from this bottle!
Suigetsu didn't dare swallow the last bit of… spit that was still left in his mouth nor was he able to look Sasuke in the eye the entire day. Suigetsu knew exactly who Karin was collecting spit samples from and he couldn't quite forget the taste afterwards…
Characters © Masashi Kishimoto