The Unique Distance Between Fellow Fans#

Eripiyo and the other fans who support ChamJam often spend time together and attend events as a group. However, they are not exactly close friends.

Instead, they are connected through a shared passion as oshi-katsu（推し活）companions—people united by their support for the same idols. Because of this, their conversations often use polite language while still feeling friendly and relaxed.

For Japanese learners, this provides an excellent example of how Japanese people can maintain a comfortable social distance without sounding cold or unfriendly.

Source: Hirao Auri , Oshi ga Budokan ittekuretara shinu (TOKUMASHOTEN)

A High Amount of Polite Japanese#

Many idols in the series also speak politely to their fans. (Some idols choose a more casual style to create a sense of closeness, but Maina and others frequently use polite speech.)

As a result, the manga contains a relatively high amount of teineigo (polite Japanese), making it particularly accessible for beginner learners who want exposure to natural, everyday polite conversation.

Source: Hirao Auri , Oshi ga Budokan ittekuretara shinu (TOKUMASHOTEN)

The Image of “Underground” in Japanese#

In English, underground culture can sometimes sound cool, artistic, or rebellious.

Japanese also uses 地下 to describe activities outside the mainstream, but the word often carries additional feelings of:

• obscurity
• marginality
• instability
• social awkwardness
• lack of recognition

For many Japanese people, 地下 suggests something that exists outside the spotlight.

It is not necessarily illegal or dangerous, but it often feels slightly removed from the “proper” or “official” world.

Examples include:

• 地下ライブ (small underground concerts)
• 地下劇団 (small independent theater groups)
• 地下格闘技 (unofficial fighting events)
• 地下アイドル (underground idols)　
• 地下芸人（struggling comedian）

In each case, the activity exists, but without the prestige, visibility, or legitimacy associated with major institutions.

Not Criminal, but Not Quite Mainstream#

One interesting aspect of Japanese 地下 culture is that it often occupies a gray area in the public imagination. People do not usually think underground idols are doing anything wrong. However, the word can create a subtle feeling that participants are pursuing something uncertain, unconventional, or difficult to explain to outsiders. A major idol performing at the Budokan arena represents success and social recognition.

A 地下アイドル, by contrast, may perform for a few dozen fans in a small venue. The gap between those two worlds is enormous.

Because of this, the word 地下 often evokes a sense of struggling outside the center of society.

Why Fans Are Drawn to It#

Ironically, this lack of status is part of the appeal. Fans are not supporting someone who has already succeeded. They are supporting someone who might succeed one day. The emotional reward comes from watching growth, sharing hardships, and feeling that their support genuinely matters.

This is one reason why the Japanese word 推し (oshi) became so closely connected to underground idol culture. Fans are not merely consumers—they see themselves as active supporters helping someone pursue a dream.

What It Means for Learners#

For learners of Japanese, 地下 is a useful example of how words carry cultural associations beyond their dictionary definitions. In many contexts, 地下 does not simply mean “below ground.” It can suggest something hidden, overlooked, unconventional, or struggling outside the mainstream. That is why the title Oshi ga Budokan Ittekuretara Shinu feels so meaningful.

The story is not about famous stars at the top of the entertainment world. It is about people who begin in the “underground”—far from recognition, far from success—and the fans who choose to believe in them anyway.

Understanding that nuance helps explain not only underground idols, but also a broader Japanese fascination with cheering for those who have not yet reached the spotlight.

Unusual Nicknames#

The series features characters with distinctive nicknames such as Eripiyo and Kumasa. The nuances behind these names may be difficult for beginner learners to fully understand. Fortunately, many Japanese readers react to them in much the same way:

“That’s kind of a strange nickname, isn’t it?”

So don’t worry too much about analyzing them. They’re simply part of the quirky charm of the series and its characters.

Source: Hirao Auri , Oshi ga Budokan ittekuretara shinu (TOKUMASHOTEN)