infuriating that it's been 15+ years and so many people still get Roy killing Lust wrong
"it's ironic that Lust was killed by a womanizer" "Lust was killed by a man who lusted after power" NO! Lust was killed by a man who did it because of love.
It's ironic that she was killed by a man who uses his (false!) public reputation as a womanizer to conceal the fact that he is one of the most steadfastly loyal people in Amestris. It's ironic she was killed by someone whose entire motivation revolved around gaining the power to help others. It's ironic that he killed her for threatening his people.
Lust was killed because Roy refused to let Havoc die, because he refused to let Riza throw away her life. He killed her because he refused to die without making sure the people he loved were safe. Lust was killed because of love. That was the point.