Es stands for "Embryo Storage". She's two years old in the game.

Originally, I was going to say that this game feels like the visual novel you'd get out of a happy meal, but there's too many scenes of nude underaged girls for that. Even if you give a shit about the story (aka should be put on a list), the news snippets you have to constantly be on the lookout for destroy and flow to reading that you could possibly have.

I've played Es in every game Arcsys has thrown her in, and even I'm like "yeah, they gotta take this game out back and put it down like ol yeller". Even for people who don't think Mori is a Shouzou Kaga-tier creep, you're gonna have a better time reading the wiki.