Elizabeth is a friendly High Slug. She can join you after a battle.
Elizabeth: "Let's go for a stroll. Come on, won't you take me somewhere?"
Lime: "Whoa, you're a big slug..."
Elizabeth: "I'm what? This child... Can I eat her?"
Lime: "Ah! No! Don't!"
Sonya: "Hey! Stop picking on her!"
Melk: "Big sister..."
Elizabeth: "Oh, what a good girl. I'll give you a little love."
Melk: "Squishy squishy."
Elizabeth: "Slimy slimy."
Elizabeth: "Hello boss. Today is nice and damp isn't it?"
Melty: "I don't think the title of boss really fits us."
Melty: "But we don't seem like a mid-boss..."
Melty: "What's a mid-boss? Sounds scary..."
Elizabeth: "(Actually, I think you were a mid-boss.)"
She is required in the "Slug Stage" scene.