This man is Sakura Miko’s boyfriend. Remember Miko’s 3 month break in 2020? Well 3 months is the same length as Japans maternity leave. Usan is the father of Miko’s child.
Meet Usan, sales manager at Cover Corp.

mysterious sales manager USAN/ICHIBACHI who is connected to fps team FNATIC
his profile "ピンク髪" means Pink hair(Now removed)
https://i.imgur.com/Es6H4Zq.jpg
https://i.imgur.com/76zG23t.png
https://i.imgur.com/klJUQk2.png

Tokyo Tourism Ambassador's note confirms the existence of "U-san".
https://note.cover-corp.com/n/nd5bda641e7df
He handpicked Miko to be part of the group. Gura has the most subs and Mori has a record deal deal. So why pick Miko? Because Miko dates the project lead.
Goes on at length as to how Miko was the perfect pick for the project. Said very little about Gura or Mori

Horizontal
https://i.imgur.com/sPxYbSI.jpg
https://i.imgur.com/iayBtrl.jpg

Pink hair in attendance at YAGOO's first pitch ceremony.
https://youtu.be/Ek_hJRXYqE0&t=83

(been to Kyoto with Miko https://i.imgur.com/E1au8zd.jpg)

From STEAM, "USAN=Yuki Matsumoto" ?
https://steamid.uk/profile/76561198063423223
https://i.imgur.com/ber1Wpg.jpg
https://i.imgur.com/K3LCu6j.jpg

"Yuuki Matsumoto" confirmed in Sakura Kakumei project
https://game-i.daa.jp/? EF%BD%9E%E8%8F%AF%E5%92%B2%E3%81%8F%E4%B9%99%E5%A5%B3%E3%81%9F%E3%81%A1%EF%BD%9E#h7542dc4

Does this surprise you? It shouldn’t. Sakura Miko has been a whore all her life. Here are some voicepacks her roommate sold pre-Hololive where she sucks cock and talks about the taste of cum.
https://www.dlsite.com/maniax/work/=/product_id/RJ163805.html
>ジャンル 淫語 催眠音声 ロリ 露出 逆レイプ 男性受け
https://files.catbox.moe/ecy8v8.mp3

https://www.dlsite.com/maniax/work/=/product_id/RJ164622.html
>ャンル 淫語 催眠音声 耳かき SM 逆レイプ 男性受け