Bowser (and Bowsette sortof) belongs to Nintendo  
Bases by DoraAir and DianaMur
 
 
Bowser: Guards, whos at my castle? Who demands to see me?
 
Guard: A queen from a faraway land, your highness. She requests to aid you in your takeover of the kingdom.
 
Bowser: Let her in.
 
[Doors open and Bowser looks from his throne as his guest enters in. He got a good look at her. She was no ordinary queen. She was also a Koopa. Her shell was a bright pink and her red hair was put back in a ponytail. Her crown reminded him a lot of Princess Peach’s. She was a pretty Koopa indeed.]
 
Guard: Your highness. Queen Koopette.
 
Koopette: It’s an honor meeting you, King Bowser. I’ve heard amazing things about you.
 
Bowser: O-Oh! Well, I am pretty special. So, you wish to aid me in defeating that plumber?
 
Koopette: Both plumbers and I’ll even help overthrow that Toadstool. I’ve admired your work for a long while, and I do look forward to assisting you.
 
 
HELLO! So proud of this dialouge!  
Heres my personal headcanon about “Bowsette”. That she’s a different character herself! A Queen from far away who helps Bowser, but the two develop a close bond and she becomes Juniors new mom. Theres also a royal wedding, while Peach supports them happily and proud that Bowser has moved on.