[asaqe]

I think it is like this

-Regius takes DNA sample from Quint to give to Zest. (Could be a medical test.)

-Zest goes and becomes a relic weapon for unspecified reasons while handing Scalleghetti the DNA sample to work with

-Scal Creates the Type Zeroes.

-Type Zeroes have Scal's DNA mixed in order to activate the OB skill.

Also on the note of vivio, maybe during the time she was making her escape (in her adult form or something, she came under attack, unleashed the massive burst attack and the strain of it forces her to remove the Relics and turn back to her child form.