The biggest block of missing old and rare ero animations from one company is Piss Comic (some titles are provided by DLsite). They are more or less motion mangas only. As it was the same artist team making it we can add the Dazzing Dream releases too.
I have found information about a missing release by Okei Publishing too.
Here´s a list / overview:
Dazzing Dream:
DDA-001 花びら満開 ムチムチナース - hanabira mankai muchimuchina^su - muchi muchi series vol. 1
DDA-003 花びら満開 ムチムチレースクィーン - hanabira mankai muchimuchina^su - muchi muchi series vol. 2 (has been posted here already)
DDA-XXX 花びら満開 ムチムチシリーズ 第三弾 ムチムチ奥さま - hanabira mankai muchimuchina^su - muchi muchi series vol. 3 (VHS serial no. missing)
Piss Comic:
PC-01 おさわり痴漢白書 PART1 - o sawari chikan hakusho PART 1
PC-02 いけない近親相姦 PART 1 - ike nai kinshin soukan
PC-03 ぬれぬれ姉妹相姦 - nure nu re shimai soukan
PC-04 おもらし恥辱少女 - omorashi chijoku shoujo
PC-05 おねだり人妻遊戯 - o nedari hitoduma yuugi
PC-06 天然物語～序章～ 西村久美 - tennenmono go ~ joshou ~ nishimura kumi
PC-07 天然物語～二章～ 西村久美 - tennen monogatari ni shou nishimura kumi
PC-08 天使物語～三章～ 西村久美 - tenshi monogatari ~ sanshou ~ nishimura kumi (has been posted here already)
PC-09 爆乳 Fカップ家庭教師 - baku chichi f kappu kateikyoushi
PC-10 へんたい病院物語 - hentai byouin monogatari
PC-11 背徳の調教生活 - haitoku no choukyou seikatsu
PC-12 通勤通学 妄想学園ラブストーリー - tsuukintsuugaku mousou gakuen rabusuto^ri^ (DLsite material - available on some p2p networks)
PC-13 おさわり痴漢白書 PART2 - o sawari chikan hakusho PART 2
PC-14 どきどき近親相姦 痴漢通学路2 - dokidoki kinshin soukan chikan tsuugaku ro 2
PC-15 unknown, is there one?
PC-16 いけない近親相姦PART2 姉と弟 - ike nai kinshin soukan PART 2 ane to otouto
PC-17 痴女学園 - chi jo gakuen
PCD-003 ふたなり少女 痴漢通学路 - futanari shoujo chikan tsuugaku ro (DLsite material) (compilation)
PC-XX 姦っちまえ！TVキャスター ～筒井麗子25才～ - kashimacchi mae ! tv kyasuta^ ~ tsutsui reiko 25 sai ~ (VHS serial no. missing) (posted on A-O as Yachimae! TV Kiyasta)
PC-XX 禁断シリーズ・背徳のすすめ ～女子高寮・悦楽の園～ - kindan shiri^zu . haitoku nosusume ~ joshikou ryou . etsuraku no sono ~ - Super Illustrian Replica (VHS serial no. missing)
PC-XX DLsite compilation 1 (unknown contents - distributed via DLsite)
PC-XX DLsite compilation 2 (unknown contents - distributed via DLsite)
I have found information about a missing release by Okei Publishing too.
Here´s a list / overview:
Dazzing Dream:
DDA-001 花びら満開 ムチムチナース - hanabira mankai muchimuchina^su - muchi muchi series vol. 1
DDA-003 花びら満開 ムチムチレースクィーン - hanabira mankai muchimuchina^su - muchi muchi series vol. 2 (has been posted here already)
DDA-XXX 花びら満開 ムチムチシリーズ 第三弾 ムチムチ奥さま - hanabira mankai muchimuchina^su - muchi muchi series vol. 3 (VHS serial no. missing)
Piss Comic:
PC-01 おさわり痴漢白書 PART1 - o sawari chikan hakusho PART 1
PC-02 いけない近親相姦 PART 1 - ike nai kinshin soukan
PC-03 ぬれぬれ姉妹相姦 - nure nu re shimai soukan
PC-04 おもらし恥辱少女 - omorashi chijoku shoujo
PC-05 おねだり人妻遊戯 - o nedari hitoduma yuugi
PC-06 天然物語～序章～ 西村久美 - tennenmono go ~ joshou ~ nishimura kumi
PC-07 天然物語～二章～ 西村久美 - tennen monogatari ni shou nishimura kumi
PC-08 天使物語～三章～ 西村久美 - tenshi monogatari ~ sanshou ~ nishimura kumi (has been posted here already)
PC-09 爆乳 Fカップ家庭教師 - baku chichi f kappu kateikyoushi
PC-10 へんたい病院物語 - hentai byouin monogatari
PC-11 背徳の調教生活 - haitoku no choukyou seikatsu
PC-12 通勤通学 妄想学園ラブストーリー - tsuukintsuugaku mousou gakuen rabusuto^ri^ (DLsite material - available on some p2p networks)
PC-13 おさわり痴漢白書 PART2 - o sawari chikan hakusho PART 2
PC-14 どきどき近親相姦 痴漢通学路2 - dokidoki kinshin soukan chikan tsuugaku ro 2
PC-15 unknown, is there one?
PC-16 いけない近親相姦PART2 姉と弟 - ike nai kinshin soukan PART 2 ane to otouto
PC-17 痴女学園 - chi jo gakuen
PCD-003 ふたなり少女 痴漢通学路 - futanari shoujo chikan tsuugaku ro (DLsite material) (compilation)
PC-XX 姦っちまえ！TVキャスター ～筒井麗子25才～ - kashimacchi mae ! tv kyasuta^ ~ tsutsui reiko 25 sai ~ (VHS serial no. missing) (posted on A-O as Yachimae! TV Kiyasta)
PC-XX 禁断シリーズ・背徳のすすめ ～女子高寮・悦楽の園～ - kindan shiri^zu . haitoku nosusume ~ joshikou ryou . etsuraku no sono ~ - Super Illustrian Replica (VHS serial no. missing)
PC-XX DLsite compilation 1 (unknown contents - distributed via DLsite)
PC-XX DLsite compilation 2 (unknown contents - distributed via DLsite)
