You know. I can't help but think that the environment might be a factor.
Perhaps if two trainers got together and had duels in a koi pond with these things they could level it up to a point where summoning one did not amount to sadism.
Last weekend I was bored and didn't have the energy to do anything much, and there was nothing of interest on Netflix* and I didn't feel like poking around the current anime season, so I thought, why the hell not?
I've been going through about four episodes a day since then and just started on Next. Plan to go the whole way through - four full seasons, six OVAs, and five movies. And maybe Lost Universe as well, which is kinda-sorta related.
I've already started having dreams set to the Slayers score.
* Netflix Australia has about one tenth the content of the US version. It's pretty sad.