[Hazu]

You do lose exp when pked. I tested.
You cant attack guildmates in abyss. Unless your an archer and aoe poisons.
you lose about 10% of the exp you naturally lose by being killed by a mob. I think thats right.. not sure my math really sucks.

Every time youkill someone you get a kill point.

And honestly I if I run into a low lvl in the 7x abyss I'll prob kill him/her.... (It angers me that much)