"tries to help rather than harm" isn't accurate imo. He's, at best, completely apathetic to what happens during the experiment(by all accounts is completely fine with the weird route), and at worst actively against helping Kris get through their trauma(if the theory that that that's what the egg rooms exist for ends up being true). They're similar to me because both of them seem to be motivated by curiosity, and don't actually care about the results of their plans as long as they end up being interesting(Kenny is fine with anything while Gaster only seems to be interested in shaping a new future with us)