From Boys On Boys Love:

Haruhiko's older brother Seiichi suddenly stops sending letters in the middle of investigating the mysterious organization called PARK. Haruhiko crosses over to Hong Kong to pursue the whereabouts of his brother and encounters detective Kuwan who continues to investigate PARK. Kuwan comforts Haruhiko who is shaken with anxiety and loneliness and vows to protect Haruhiko with all of his power. But, because of his good looks, Haruhiko gets captured as a pet of PARK...!?