Beaten at their own game - Winner Privilege - Begrudgingly>Enthusiastic/ Accepting

Beaten at their own game - Might makes right however there many kinds of strength in this world. The challenger can challenge anyone into a contest but the challenged can choose what the contest is. A track field player would obviously choose a race while a chess prodigy would choose a chess game. If the challenger wins then they get the prize of the loser's body (for some time). If they loss, they will have to try again after some time.

If the challenge involves a group fight then the condition applies to the subordinates of both sides as well however the team leader gets first pick.

Winner's Privilege - You have beaten them at their own game and have proven your superiority over them. In that case, it is proper that you pass your genes to your children. You get one try to either impregnate or be impregnated by the loser in order to let your clearly superior genes pass along.

Begrudgingly>Enthusiastic - Your targets will will only begrudgingly accept your seed and may often only accept a shot or two. But if you keep on winning against them their attitude towards you changes, they soon become enamored with the idea of carrying your children. They will become your devoted partners and you don't have to challenge them anymore. Of course if you lose against them even once before that, you have to start again from scratch.

Accepting- The Public accepts this a fact of life and will not interfere as long as the winner does not interfere with non-participants to the contest.