Boku No Natsuyasumi 4 - Setouchi Shounen Tanteidan, Boku To Himitsu No Chizu ROM Download for Playstation Portable (PSP). Boku No Natsuyasumi 4 - Setouchi Shounen Tanteidan, Boku To Himitsu No Chizu game is available to play online and download only on Roms Games. Boku No Natsuyasumi 4 - Setouchi Shounen Tanteidan, Boku To Himitsu No Chizu ROM for Playstation Portable download requires an emulator to play the game offline. This Game is English (USA) Version and is the highest quality available.