In The Meantime
The Masked Marauder was an utter egomaniac, obtuse to his daughter's needs, a daughter who wasn't exactly at peace with this, and struggled to come to terms with this for ages. This made a certain character have some unwholesome ideas.
Cass has always been considered cold and insensitive. She doesn't dare to think about it, but it's most likely due to being raised by an eccentric. She learned quickly to quit being vulnerable or sympathetic, at risk of feeding her father's ego, the absolute last thing she wants to do. Wade pokes and prods this sensitivity, playfully. Cass is prepared to kick him in the nuts.
It started with him jokingly suggesting that he replace her jackass father, and kill him too, she's unsure how to respond to this. Then, he crosses the line, again, again, and again, into unexplored territory. He boasts a lot about how much better he is. Cass rolls her eyes, but finds herself anticipating those moments where he pushes her boundaries. She thinks he's attractive, in a weird way.
She notices the way he flinches at the mere mention of fatherhood. He lies awake, watching, when Cass has bad dreams. He goes quiet when she says "You'd be a good dad." Gears are turning in his head lately, she's unsure what about.
Wade insists on her holding his finger while walking, patronizing her, spoiling her. It irritates her, but she says nothing.
He starts being overbearing, asking her if she brushed or washed properly, insisting he help her. Cass screams and slams the bathroom door on his hand.
He buys her an oversized pair of fluffy pajamas, making sure she wears it to bed, tucking her in, kissing her forehead. Cass swats him away, scowling before eventually falling asleep.
She begins to worry when these strange behaviors seem to delve into less-than platonic territory. Kissing and holding hands, while he says she's such a good, perfect girl. Cass kicks him in the jaw, sulking under the covers.
She says "...I'm not even going to entertain that." when he starts calling himself "Daddy." After enough tormenting, she gives in sometimes, and notices a complete shift in the atmosphere, wondering why he's suddenly so intense. Her tail dances anxiously.
Cass starts leaning into it, just to see his reactions.
Wade is caught off-guard by her squeezing his thumb of her own volition, staring at him with an anxious expression, breaking eye contact, like she'll get in trouble. A sly grin creeps up his face, he takes this as permission to stop holding back.
They sleep together, with Wade enveloping and squeezing her, his hands sometimes wandering and groping. Cass wonders if there's any going back, when his hands slip under her pajama pants while cradling her, talking her through it.