If I was an omni, I would modify my own body to match the erotic preferences of the people I meet. But I would never remove any part; I would instead keep adding and adding and adding parts, maybe give birth to an extra remote-controlled body if absolutely necessary.

The end result: everyone would end up being completely enthralled by my beauty (or at least the beauty of the specific parts I grew just for their pleasure). I would eventually replace the planet with my own fleshy mass, before encouraging my subjects to launch an intergalactic crusade to provide me with more living beings to seduce. Not that I need their help, but I like to see them work for me.

After that, who knows? Maybe I'll let myself evolve to the point that I can seduce time and fuck my way into the past, to retroactively seduce everything that ever existed.