An Emotional Tissue Box is someone you can come to, to talk about your feelings and emotions. They are there for you, and they are like a tissue box because they quell your tears.
To show how someone is such a good tissue box, call them by a really nice tissue box brand name, like Puffs Plus.
Jonny Waffle: Avery, you dah best.
Avery: I'm here for you man.
Jonny Waffle: You're like Puffs Plus, you Emotional Tissue Box.