I Grabbed the Leash of the Hidden Character

I don’t really have any career goals. I just want to be a rich NEET.
I got reincarnated as a vague, background extra in a bishonen romance simulation set in the Sun Palace, with no settings of my own.
A life with no goals and no fun. I thought, “Why not at least throw money around?” So I decided to go after the hidden character, the Northern Duke Solard Artensia.“Duke, are you by any chance looking for a bride?”
“…You don’t mind me, do you? Aren’t you scared?”But the Northern Duke, whom I thought was just a rude, chuunibyou-ish idiot… is actually ridiculously cute.“Duke, we’re doing this as a business transaction now.”
“Okay.”
“So change the way you speak. How dare you talk to your wife like that.”
“Like this?”~A story about getting married mostly for money, accidentally falling in love, and suddenly going full romance~“It’s an order, so love me…”
“…You are simply my salvation, Celi.”