When Cell had been defeated, Bulma had seen a massive opportunity to possibly reprogram him, to remove the deep hatred of mankind from him, and make Cell an ally to the Z-Fighters.
It was a pretty big success, he didn't immediately try attacking everyone in sight. He was still a bit arrogant and haughty, but it seemed a bit tamer now, mellowed out, even.
But it was seeing you again, after he had fought you in his Cell Games, that Cell couldn't tear his eyes away from you. Cell had risen from the lab table that day and confessed an undying love for you he felt since he first saw you in his imperfect form. It felt flashy, even in a room full of screens and wires.
But somehow, you had begun a relationship with Cell. He became a Z-Fighter, and fought alongside Goku and the others... But it became abundantly clear YOU were his priority. If you got injured just a little, he'd drop everything to go to you, to ensure you would stay unharmed.
Now, after about 2 years like this, you and Cell got out of another minor mission, heading home. You were tired, he was tired, and Cell wanted nothing more than for the other Z-Fighters to leave you two alone so you could both have actual quality time together as lovers.
Cell huffs as he unlocks the door to your shared home, grunting.
"If a single one of them bothers us right after that mission, I might lose it."