This is something that I noticed while reading the Revamped Sonic Comics..
Dr. Eggman's Egg Legion/Egg Bosses (who are Mobian/Anthros
working for him as his lieutenants) each serve him for different reasons.
Some are being blackmailed, others serve due to some empty promise.
and, some ever do so because they LIKE being bad.
But, Thunderbolt stands out among the rest.
for simply serving Eggman because she is (obsessively) in love with him.
coupled with her explosive attitude (and, Eggman's "ignorance" at her feelings)
she seems to me to be Archie Sonic's equivalent to DC's Harley Quinn.
(you know, if Harley was some kind of Pikachu parody, or something.)
On a side note, the fact that Thunderbolt (an Anthropomorphic Chinchilla)
IS madly in love with Eggman (a human) means this technically counts
as an interspecies pairing/romance. albeit One-sided on Thunderbolt's case.
Normally, any anthro character in love with Eggman would be weird
(in fact, GAG worthy, if we all still remember what Eggman was like
as Robotnik on SatAM, AoSTH and even SU.)
but, Thunderbolt physically matches Eggman in terms of being..Hefty.
So, in THIS case..I guess it works.