Mahoto Watanabe
Person · male · Japan · Yonōzu · born 1992
former Japanese YouTuber and rapper
Also known as ワタナベマホト
Timeline
1990s
Biography
Biography
Mahoto Watanabe (ワタナベマホト, Watanabe Mahoto; born December 8, 1992) is a former Japanese YouTuber and rapper. He was part of the hip hop group Kaiware Hummer, releasing music under the stage name Bema.
Watanabe first began posting videos on Nico Douga in 2007 and transitioned to YouTube in 2010, becoming one of the first YouTube personalities on YouTube Japan. He gained popularity with his radical video style, but he was also known for his caring personality for his junior YouTubers, who called him "Oyakata". He is famous for having trained up popular YouTubers such as Tokai On Air, Avntis, and Hekitora House.
In January 2021, Watanabe allegedly solicited nude photos from an underage fan, which subsequently caused his agency Uuum to drop him as an act and YouTube to permanently ban his channel. In March 2021, he announced he was retiring from YouTube.
Career
On November 7, 2007, when Watanabe was in middle school, he posted on Niconico under the username Sashiman (サシマン). Watanabe began uploading to YouTube in 2010.
In 2013, after signing with Genesis One, Watanabe became a member of the hip hop group called Kaiware Hummer with his fellow member Imiga and began his career as a rapper. Kaiware Hummer released their debut album, Beginner, under Neo Kinder Records on July, 12 2014. In addition, Watanabe released his debut solo album, Shinryakuteki Sukima, on November 26, 2016. In 2015, Watanabe made his acting debut in the Squash Films' drama titled Dancing Office Worker.
In 2018, Watanabe left Genesis One and signed with Uuum as his network. By June 2019, he had over 2.7 million subscribers on his main channel. After getting arrested on suspicion of battery in the same month, his activities were cancelled for the remainder of the year, including a new label contract between with Avex and an appearance of Kaiware Hummer at A-Nation 2019, while he remained at Uuum to do clerical work. On February 7, 2020, Uuum announced that Watanabe would resume activities on February 14, 2020 on a new channel.
On January 22, 2021, Uuum announced that Watanabe had been dismissed from the agency after confirming he solicited nude photos from an underage girl. On January 28, 2021, YouTube suspended his channel for community violations. Following the events, on March 2, 2021, Watanabe issued an apology on Twitter and also announced he was retiring from YouTube.
Since his retirement from YouTube, Watanabe started editing videos for Gardman, a YouTube channel with 2 million subscribers, earning him a million yen a month.
Personal life
On January 21, 2021, Watanabe announced that he was marrying actress and former Keyakizaka46 member Yui Imaizumi and that they were expecting a child. The child, a daughter was born in June 2021. Following Watanabe's 2021 arrest, Imaizumi announced in July 2021 that she would not be registering their marriage and that she would be raising the child herself with support from her family.
Legal troubles
On June 2, 2019, Watanabe was arrested on suspicion of battery. He had reportedly beat a female acquaintance and stomped on her face during an argument while he was intoxicated. On June 19, 2019, he issued an apology and also claimed he reconciled with the victim. On July 18, 2019, Uuum later stated that Watanabe's activities would be suspended, including Kaiware Hummer's appearance at A-nation 2019. Instead, he would be doing clerical work within the agency until December 31, 2019, though there were no immediate plans of him returning in January 2020. During this period, he was also prohibited from drinking.
On January 21, 2021, the same day where Watanabe announced his marriage to Yui Imaizumi, Japanese YouTuber Korekore posted a live stream video where a 15-year-old girl alleged Watanabe had solicited nude photos from her and then blackmailed her with them, with screenshots of private messages from November 2020. On January 22, 2021, Uuum announced that Watanabe confirmed the reports and was dismissed from the agency. The victim later contacted the police, which resulted in Watanabe being arrested on suspicion of forced child prostitution and possession of child pornography on March 17, 2021 after investigation. He was released on April 2, 2021 and indicted by the Tokyo Metropolitan Police Department on April 22 of the same year. On June 14, 2021, he was fined ¥500,000.
On March 22, 2024, Watanabe was arrested on suspicion of allegedly assaulting his ex-wife, including pushing her to the ground, on March 21.
Discography & profile
Normalised profile
Percentiles are computed over every artist in the database, so a tier-3 artist can still sit in the 95th percentile on a single axis.
| Metric | Value | Percentile |
|---|---|---|
| Wikipedia language versions | 3 | 16th |
| Spotify monthly listeners | — | no data |
| Release groups in DB | 0 | 0th |
| Studio albums | 0 | 0th |
| Awards recorded | 0 | 0th |
| Timeline events | 1 | 40.6th |
| Recording span (years) | — | no data |
| Genres | 0 | 0th |
Percentiles are computed at render time; missing values mean the artist has no data on that axis.
Discography (0 release groups)
No discography rows stored yet
MusicBrainz enrichment for this artist is still pending. Release groups appear here once it runs.
Stats & PK
Percentile within all 23,672 published artists.Put Mahoto Watanabe head-to-head →
| Metric | Value | Percentile |
|---|---|---|
| Wikipedia language versions | 3 | 16th |
| Spotify monthly listeners | — | no data |
| Release groups in DB | 0 | 0th |
| Studio albums | 0 | 0th |
| Awards recorded | 0 | 0th |
| Timeline events | 1 | 40.6th |
| Recording span (years) | — | no data |
| Genres | 0 | 0th |
Awards & honours
Where this record comes from
core—wikidata · CC0 · retrieved 10 October 2026
https://www.wikidata.org/wiki/Q84581458seed-list—wikipedia · CC BY-SA 4.0 · retrieved 10 October 2026
https://en.wikipedia.org/wiki/Mahoto_Watanabebiography—wikipedia-en · CC BY-SA 4.0 · retrieved 10 October 2026
https://en.wikipedia.org/wiki/Mahoto_Watanabe
Why this artist is in the database
- List of hip-hop musicians
Tier rule: curated genre/region list
Image: no portrait (not displayed: the licence credit is missing)
Wikidata: Q84581458 · MusicBrainz: —
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