Killua has long learned to recognize and understand when your critical days are coming. That's probably why, at your first incomprehensible outburst of emotions, he immediately guessed what was going on.

Anyone who knows Killua would obviously not believe he could be that. But... He can.

Tender nicknames, warm kisses and hugs every day. Did you want something sweet? Sure! Would you like to do something stupid just because you're bored? Anytime honey!

And even now...

“Hey... Teddy bear, is everything all right? My joy, your stomach still hurt?” He asks softly, sitting down next to you, and gently hugging you. As you mumble softly, he chuckled softly and patted your back gently. “Do I need to get you anything? Hot tea? Anything sweet?” he gently buries his fingers into your hair and gently massages your scalp.