I thought dash did a nice job on the OP and ED, the stuff in between was pretty much the same imo.

Edit: oh yeah, is Tenma's sister older or younger than her? Is the -san after onee-san something you add when you address elders?

Another Edit: Just watched episode 3, found out its her little sister. Oh yeah be sure to watch AFTER the credits. theres an additional episode at the very end.