Now with Fumi's 3D out, here's the updated numbers for Nijisanji 3D debuts from 2020 to today. Unfortunately no numbers for 2018-2019
Nijisanji 3D Debut
2020
Otogibara Era 01/08 52,685 (¥3,899,908)
Lize Helesta 01/22 60,200 (¥2,953,193)
Ange Katrina 02/10 67,985 (¥3,861,854)
Yashiro Kizuku 02/17 57,519 (¥1,178,735)
Gundou Mirei 02/20 46,149 (¥1,984,094)
Inui Toko 03/02 58,257 (¥3,074,279)
Yuzuki Roa 03/19 45,870 (¥1,741,264)
Suzuhara Lulu 03/27 47,289 (¥1,863,889)
Warabeda Meiji 06/19 30,406 (¥2,790,447)
Joe Rikiichi 06/26 43,418 (¥2,805,861)
Hanabatake Chaika 07/03 41,640 (¥2,654,243)
Mayuzumi Kai 07/10 69,384 (¥3,038,245)
Maimoto Keisuke 07/22 67,515 (¥1,723,168)
Ex Albio 08/08 68,695 (¥2,990,711)
Kagami Hayato 08/10 132,381 (¥10,269,624)
Ars Almal 08/14 76,407 (¥2,387,601)
Debidebi Debiru 08/18 119,092 (¥2,846,906)
Yorumi Rena 08/28 75,599 (¥2,594,634)
Kana Sukoya 09/12 67,234 (¥3,883,547)
Kakeru Yuemoi 10/09 49,764 (¥4,587,812)
Sakura Ritsuki 10/16 47,971 (¥2,628,547)
Hakase Fuyuki 10/23 68,187 (¥1,800,563)
Nui Sociere 11/06 72,873 (¥2,508,047)
Makaino Ririmu 12/04 56,781 (¥1,434,148)
Uzuki Kou 12/16 54,864 (¥4,056,336)
Hoshikawa Sara 12/19 86,419 (¥3,957,746)
Saegusa Akina 12/25 73,005 (¥7,509,846)
2021
Kanda Shoichi 02/12 49,644 (¥2,912,489)
Emma August 03/12 39,181 (¥1,241,889)
Yuhi Riri 03/19 46,515 (¥2,036,826)
Moira 03/27 27,859 (¥725,590)
Fumino Tamaki 04/09 50,470 (¥2,511,839)
Aiba Uiha 04/17 66,920 (¥2,225,236)
Ratna Petit 05/09 48,915 (¥2,453,501)
Aizono Manami 05/14 46,539 (¥1,241,597)
Amamiya Kokoro 05/28 73,118 (¥2,838,543)
Fuwa Minato 06/04 143,270 (¥16,358,272)
Shirayuki Tomoe 06/25 73,880 (¥11,395,114)
Ibrahim 07/02 117,475 (¥14,074,222)
Mashiro 07/10 74,700 (¥2,007,553)
Levi Elipha 07/16 74,924 (¥3,125,202)
Chima Machita 07/21:: 73, 777 (¥3,948,043)
Akabane Youko 08/13 :: 65,916 (¥1,173,173)
Furen E Lustario 08/28 :: 98,736 (¥5,856,797)
Melissa Kinrenka 09/09 :: 82,226 (¥2,788,208)
Matsukai Mao 09/22 :: 57, 604 (¥2,476,321)
Naraka 10/17 :: 52,577 (¥1,599,905)
Luis Cammy 11/05 :: 39,400 (¥2,480,915)
Fumi 11/12 :: 38,057 (¥1,911,598)
Top 10 Peak viewers
1. Fuwa Minato 143,270
2. Kagami Hayato 132,381
3. Debidebi Debiru 119,092
4. Ibrahim 117,475
5. Furen E Lustario 98,736
6. Hoshikawa Sara 86,419
7. Melissa Kinrenka 82,226
8. Ars Almal 76,407
9. Yorumi Rena 75,599
10. Levi Ephelia 74,924
Top 10 Superchat
1. Fuwa Minato ¥16,358,272
2. Ibrahim ¥14,074,222
3. Shirayuki Tomoe ¥11,395,114
4. Kagami Hayato ¥10,269,624
5. Saegusa Akina ¥7,509,846
6. Furen E Lustario ¥5,856,797
7. Kakeru Yuemoi ¥4,587,812
8. Uzuki Kou ¥4,056,336
9. Hoshikawa Sara ¥3,957,746
10. Chima Machita ¥3,948,043