the tv series was much much much much lighter than the OVAs so there wasn't really that much censorship, but the censoring was annoying, a good watch tho.
The OVAs follow the fate of the siblings while the TV series follows the manga and introduces a few more interesting characters, including a girl that likes to piss on the main guy

... i really hope you meant piss off =P I may just hold off on the DVD's for the TV series. Does any group plan on doing them?
I do have to get the newer OVA epps though i think i only had the first few. I actually remember reading the first several chapters of the manga to compare it to the first couple OVA episodes. Christ that was some graphic stuff. I still remember the turtlehead wakeup, and the absurd bathroom scene with the broken wrist >_< LOL, i remember watching it and going 'did they just show... juices?'
uhm no she literally does that, and
looks like she develops a fetish like that, she doesn't do it on purpose tho, it first happened when she just wanted to go to the toilet and in a strange twist of events it just happened
it's not really something bad she does, but for some strange reason... well you will see it in the show, it's really funny every time ;]
and yes they do show juices in the ova's, thats why I say, it's much much lighter in the TV series, actually, aside from what's censored, there isn't much of echii.
i think there will be 2 more OVAs, the DVD releases of the TV show, and maybe, just maybe, a second season, which I wouldn't skip ;]