Spoilers:
Giovanni is gonna make an entry soon. The most awesome villain of all in the Pokemon regions.
The list I composed of girls are:
Kanto
Eldest Sensational sister, Sabrina, Daisy ( Oak granddaughter), Solidad ( Brock childhood friend)
Johto
Jasmine, Clair, Whitney,
Hoenn
Flannery, flying gym leader, Roxanne,
Sinnoh
Cynthia ( favourite of most people),
Aurea( professor), Elsa, Skyla,
Kalos
Dianthe ( kalos champion), bug gym leader
And many more
I probably missed some so these days think of possible pairing with any one of these or other Pokemon characters.
See you later on Monday