Does anyone here have any idea how bonus attack or Defense is calculated?

The game is not clear at all on how bonuses are tallied.

I'm running an all Demon team and I'm going on the assumption that the stated Character bonuses only effect allies and not the characters themselves but I'm in no way sure.

It could also be possible that bonuses only effect allies that are other players that you team with.

I hope this this gets made more clear with latter updates.