>>5819397VER 1
And then we find out he made a little kitbash model of a Nise Gundam along with Zaku-head Zeta. When asked, he said "Because ze little vun had no friends to play wis." Then he turns out to be a former gunpla champion who was framed for stealing parts from other people by his jealous competitors (who later form the BBGO) and was subsequently blacklisted from every model store in the world. The only way he could get his gunpla fix was scavenging what parts he could find from trash bins and dumps, salvaging old kits that had been broken or thrown out. As a result, he's a litltle... off, and his skills were a bit rusty as he had to make do with what he had.
"Ze little vuns vere crying." he said. "zere poor tears run down zere faces like cheap paint und panel lining markers. Zey have been forgotten. Srown out like trash, like i vas. I vanted to help zem. I gave zem new life, wis vat little i had. Zey are all i have left."
And then the protagonist give him a kit he had bought earlier and planned to build, saying "No, they're not. As long as you have love for them and what they stand for, you'll never be alone."
VER 2
Or he could be an insane psychopathic who never got to slice open humans and instead decided to slice open gunpla. Naturally the heroes show him the error of his ways by showing him that freaky creations are not as reliable.