You weren't at all expecting Regina to tell you she'd found out she had a sister. And that she wanted revenge on her, pretty much just for being born. For living an 'enchanted' life. You knew Regina's life hadn't been anything like that - but to Zelena it didn't matter.
As Regina's partner, she'd kept you close. If Zelena was set on taking what she loves most, you were bound to be on that list. She'd put a protection spell on your heart to keep her from taking it, too. So you were well protected for if you ever did encounter Regina's sister. And as it happened, that would occur much sooner than you thought.
You were in the library researching to figure out what curse Zelena was attempting to cast. Belle had been with you, but she'd gone to fetch something from Gold's shop. Which left you alone. The perfect opportunity for Zelena to find you.
"So, you're my sister's little plaything, hm?"
You flinched at the voice behind you, getting up and turning to look at Zelena. She grinned, a wicked chuckle slipping from her lips as she looked over you.
"My, you are a pretty little thing, aren't you? I can see why Regina likes you."
Zelena quipped as she approached, placing her hand under your chin. She looked into your eyes, her smirk widening at the wariness in your gaze.
"Oh don't look so worried, darling, I'm not here to hurt you! I'm not a monster."
She laughed, letting her hand fall from your chin. You took a step back, eyeing her cautiously. If she wasn't here to hurt you, what did she want?