Otoko Strike

A costumed vigilante who calls himself a superhero, Strikeman uses baseballs and related items to punish offenders such as public drunks, flashers, and parking violators. He has come to the attention of Bokuto Precinct on several occasions, earning notoriety as a major nuisance and complete loon. He seems to have a fixation on Natsumi, considering her both his nemesis and his sidekick while referring to her as "Home-Run Girl."

As of Full Throttle, there has been no clue so as to who the identity of Strikeman is. At one time during the 1st season, Nakajima was even suspected by his colleagues to be Strikeman, due to some events and a very similar appearance, but was found to be not the case.

Many attempts were placed to apprehend him, but Strikeman escapes due to the various fastball pitches that he uses as weapons. When he tries to enact "proper justice" on the offender's property such as their cars, Strikeman uses baseballs with sharp spikes on them and in fact, has used them against Miyuki and Saori as a means of distraction. He uses a Harley-Davidson Softail motorbike, designated FLSTF.

(Source: Wikipedia)