Jet

Constant panty shots, bouncing breasts and dubious camera angles are hallmarks of an Ecchi title. These titles are usually sexualized and designed to titillate, depicting perverted themes and focusing heavily on the female body. Nosebleeds, suspicious hand positions, faceplanting into bosoms, expressive and exaggerated body parts and other tropes characterize this genre. Ecchi is all about fanservice, while Borderline H and Smut titles focus more on sexual content.

A harem includes three or more characters who potentially show romantic interest in a male protagonist. The sex, gender, or orientation of the harem members is irrelevant as long as they exclusively, or at least primarily, are vying for the affections of the same individual - who may or may not reciprocate towards one, several, or none of these romantic rivals.

Characters in these stories play a 'game' with serious consequences. Fame, fortune, power, life: any or all of these may be won or lost according to the rules of competition. The stakes and the rules may be agreed upon by parties involved, or imposed on them by an external force; either way, not following them will usually have severe consequences for the transgressor. Those who take part in the game will generally be forced to play until they win... or lose.

Mecha are self-propelling machines that are modeled after humans; some can change into multiple, non-humanoid formats as well. They're usually controlled by an internal pilot or by remote, but are sometimes sentient beings that move autonomously. A mecha's size ranges from bulky, wearable armor to a massive, towering contraption and beyond. While mecha have a wide range of applications, such as making manual labor easier, they are most commonly portrayed as heavily-armed war machines.