Twilight of the Male Wolf

Ryuichi, an office worker, gets into a fight with his girlfriend Kota, a bartender, and chases him through the streets. At that moment, he receives a violent impact on his back and collapses. Ryuichi wakes up to Kota's voice. Apparently he came to the lakeside with Kota and fell asleep. However, he only came to this lakeside a year ago when I met him...