Sess is crippled by a sneak attack and his attacker (I believe it was Naraku) stabs him through the heart, thinking him dead. Kagome finds Sesshoumaru some time after, where she discovers the sword didn't pierce his heart, for Sess is one of those rare individuals that has the heart on the wrong side of the chest. (she goes on to heal him and things progress from there...)
One of my friends had a baby recently with heart problems, and I just found out that this child is one of those few born with the heart on the right side. And then I immediately thought of this story. It's been a long time since I read it, so of course I can't find it.
Any help is appreciated.
