He loves science and just wants to be human so he can hide from G.H.O.S.T.
He basically adopted Nightshade despite Nightshade already having parents in Dot and Alex Malto.
Tarantulas cares deeply for Nightshade and gave them a Holo-form generator so that Nightshade can see him again someday, when G.H.O.S.T isn't trying to capture him.
Knows that Nightshade uses They/Them pronouns, and respects them for it, calling Nightshade his "child".
Parental Yandere.