|English Release date||12/29/12|
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| Followed by|
bug.1 is the first chapter of Biorg Trinity.
It starts off with Fujii waiting for a call from Fumiho Enomoto. Getting mad at the phone he throws it in the river next to him, believing it's causing a gap in the relationship between him and Fumiho. He then immediately regrets his decision and dives for his phone. He recovers it but catches a cold soon after. Fujii calls Shouji Hosaka who then tells Kiwako to pick him up.
The next day at school Fujii is confronted by Hosaka about where he went after Kiwako went to get him. However, while complaining about a mop injury Fujii receives the Bio Bug.
After school, we see Chieri Matsukage who before had gained popularity over her bio bug, is seen in the stall of the restroom listening to the new type of "drug" Fumiho gave her. Kiwako Confronts her knowing she using the "drug" that bypasses the law. Chieri then explains that it doesn't matter if she "goes under" as the effects will be long gone. Kiwako showing her bug then states that Chieri has "overdosed" a little, and to not let it get to her "heart".
Later on Chieri has transformed into a spider and battles Kiwako. Chieri explains how she wants to be cute and have everyone love her causing Fujii to remember her watching a boy secretly before. Obviously feeling inadequate in herself to not talk to him.
Going at full power Kiwako defeats Chieri while questioning their friendship. Fumiho is then see still in the stall trying to poo.