None. A nerdy pest sometimes makes advances toward the main female character but it is clear she wants nothing to do with him. This is all played for comedic effect.
Violence & Gore
Mild
Unlike Power Rangers, VR Troopers is syndicated, where they can push the limits of violence but still at the limits of an TV-Y7 rating.
Fantasy violence, your typical TV-Y7 level stuff. If your kids have seen the Power Rangers and you are all right with that, this show is no worse.
Profanity
None
None, just some mild heckling and slapstick stuff.
Alcohol, Drugs & Smoking
None
None.
Frightening & Intense Scenes
None
Some viewers may find Karl Ziktor's transformation into Grimlord scary, although it is very brief.
A central theme of the first season is a character's father having disappeared, which may be a bit intense for more sensitive children, but this is usually downplayed in favor of the action.