An everyman gets sucked into a survival game when a human alien kisses him and forms a psychic bond.
Forced to accommodate this new addition to his life, he adapts. Which is lucky because he's apparently a man slut to Sekirei, and several react to his psychic boner, causing him to become the Ashikabi of the North one of the 5 or 6 most powerful Ashikabi in the game.
With a strong team of pokemon Sekirei, he does what he can to play the game while also subtly fighting against it.
Also Sekirei are aliens that came to earth thousands of years ago and fucked around, resulting in most of the population being part Sekirei. Which is bad because Sekirei have a kill switch.
Also his sister and mother are massive bitches. Mostly likable though.
And the author is a woman. And one of his harem members pokemon Sekirei is a man transgendered. The Sekirei in question is not pleased about suddenly turning into a girl either..