Zettai Tenshi Kurumi-chan

Zettai Tenshi Kurumi-chan (ぜったい天使くるみちゃん, lit. Kurumi the absolute angel) was a female Japanese virtual YouTuber and a founding member of the VTuber Group, Tenmakinin ver G.

Introduction Video
This video was deleted, as were all her other videos.

4chan's /jp/ board has archived offline copies of all her videos, other than her last YouTube upload, which was online only for a few hours, in a public MEGA folder that gets posted in the Virtual YouTuber threads on that board. The archive additionally contains a copy of all her Tweets, songs posted on her mqube and videos posted on her blog.

Personality
Kurumi is an angel with a little pair of white feathered wings, red, fire-like hair who wears a black sailor suit.

When she uploaded the first video, she used a 2D avatar with FaceRig, later she made an original 3D avatar.

She usually spoke in a relaxing voice, but she became more active when playing games or singing.

Sometimes she broadcast "surprise concerts" and sung powerfully, her singing voice received high praise.

She got along well with the professional YouTubers who debuted around that time.

”Sakayake tenshi to doutei daimao” (酒焼け天使と童貞大魔王; an Angel whose throat is burned by alcohol and virgin demon) was a duo of Kurumi and Akkun-Daimao.

They, VT-212, and Inui Shinichiro also formed a team of Virtual YouTubers, called the "TenMaKiNin"(天魔機忍; Angel, Demon, Machine, Ninja).

According to Kurumi herself, the catchphrase Omae no koto nado hitonigiri! (おまえのことなど、ひとにぎり！ / I'm going to catch you! / I'm going to get a piece of you!), was intended to mean that she metaphorically grasps the hearts of the people watching her videos and she never lets them go. 

The February 14th incident


On Valentine's day 2018, Kurumi has a short exchange with Akkun Daimaou, where she ends up throwing chocolate at him. Shortly after all her account names are changed to "sorry for having been shit" in Japanese and her avatar is changed. A short time later her Twitter account and YouTube accounts are deleted. Her Steam and TwitCasting accounts remain.

Among others, Mirai Akari notices the deletion and notifies Akkun Daimaou. At this time most people believe Kurumi's accounts have been hacked. After some time Akkun Daimaou tweets that he has managed to contact Kurumi and finally relays a message from her :

"I think there are many who were surprised by the sudden occurrence. Straight to the point, the situation is that all my accounts have been taken over and deleted. Myself, I'm in a state of confusion and don't really know what to do, but for now, I'd like you all and the lambs not to worry about me and keep enjoying the virtual youtubers' contents! If I return, at that time I hope for your support once again. To the Tenmakinin who collaborated with me, to the lambs who got involved with me and the virtual youtubers: Thank you so much. It was really fun! Until the day we meet again. See you!!!!!!"

At this point, the common assumption is that her accounts have been hijacked or hacked. People post on 5ch, noticing Kurumi's other account (Steam, TwitCasting) and shortly after those posts the corresponding accounts are deleted too.

Meanwhile, in /jp/'s virtual youtuber threads, an archive of her videos is created, missing only the last video  she uploaded, which was only available for a short time and which, according to witness reports, was about about her playing Eighth Note.

Roughly 31 hours after her first accounts are deleted, her Twitter account goes back online. The handle is soon changed to @hcsrathts and the name to kkk. Some people were speculating that this was Kurumi recovering her accounts, but kkk used a tool for "dark history" purging to delete all tweets in Kurumi's account.

Shortly afterwards, kkk tweets that Kurumi will cease her activities due to family reasons, insults her, claiming she had neglected her family, and demands that her fans should verbally abuse her should she ever return. After a short time the account is deleted again and a new, locked account is created with the original account's handle, likely to prevent her from creating a new account.

Akkun Daimaou later confirms that he had previously heard Kurumi's family with his own ears on some occasion and that he no longer has any means of contacting her. After discussing matters with the other members of the Tenmakinin ver. G group (excluding Kurumi, including Gorilla), he announces that they will hope for Kurumi's return.

2018 Virtual Red and White Song Battle
On 30 December 2018, as a surprise feature to the watchers of the V Kōhaku Uta Gassen, Kurumi (along with the rest of the Tenmakinin ver G.) made a special apparition in the form of a video singing a rendition of Ryoichi Higuchi's "Roku Bun No Ichi No Yumetabi Bito Ni Sen Ni" (1/6の夢旅人2002). The video is also a retrospective of the Tenmakinin ver G. as a group (which for the first time shows their whole five members). It is still uncertain if this video signals her official return or just a one-off event.

Trivia

 * Almost all of her videos and covers are still available in archives thanks to her fans
 * Kurumi used for her streams, on the background, the song "Akireru hodo no taikutsu-sa" (呆れるほどの退屈さ) by Tsukasa Shita (志多つかさ).
 * After her sudden disappearance, Kurumi showed herself on two occasions. The first one on 23 March 2018 during a VRChat party held by Neets (using a generic red avatar), and again on April 24, 2018 for Akkun's Birthday livestream on Kaiji's channel. That stream was attended by a massive number of VTubers, and as a surprise for the Demon King, Kurumi sang for him (by appearing on the chat with the username "radangle") . Both events were referenced by the Tenmakinin ver. G 2018 special video.
 * Kurumi lent her voice for Neets' special video for 2019's April Fools. Nonetheless, her name appears blurred

Media

 * ぜったい天使くるみちゃん - Kurumi's Twitter account (now private)
 * proffy - Kurumi's profile
 * ぜったい天使くるみちゃん - YouTube (was deleted)
 * peing - Kurumi's Q&A box
 * ぜったい天使くるみちゃん - her official site (now gone)

Further readings

 * ぜったい天使くるみちゃん - Nicovideo Encyclopedia
 * ぜったい天使くるみちゃん - Pixiv Encyclopedia