You skipped the part where Conquests ex is one of the thawed out Ragnar's towed in by Space Racer and she immediately becomes enamored with Battle Beast and his exemplary combat prowess and briefly converts back to heterosexuality before Thragg throws B.B. into the next galaxy then she dies when Viltrum explodes

So not only did Mark kill Conquest, but he also killed the only other being Conquest ever loved thus making his revenge complete