If the scene starts as fully yuri, but eventually a male comes in and joins them. (The “Male Involved” tag is only used if the male is involved from the beginning of the scene.)
Series Page
Raw Chapter Link (Pages 35-50)
Rating: 3
The two FMCs very briefly have lesbian sex with each other while their boyfriends watch before they eventually join in for an FFMM Foursome.
Series Page
Rating: 4
The FMC briefly has sex with a futanari woman while her husband watches and masturbates in the background.
In Ch. 22, the MC eventually joins them for a threesome.
Series Page
Raw Chapter Link
Rating: 3
Two ghosts disguise themselves as Harino and another guy to seduce and have an FFM Threesome with Komari.
Series Page
Video Link (Rule34 Video)
Length: Long
Stays Yuri: Male Joins + Male Watches
Rating: 4
In the good ending of Kanon’s route, Kanon has lesbian sex with Utage while the MC watches for a while.
Eventually the MC joins in and the scene turns into a threesome.
Series Page
Rating: 4
After the MC leaves the room, Doyeon and Hoobae begin to fight/have lesbian sex with each other.
The MC then returns and watches for a little bit.
This will continue into the Next Chapter, where the MC joins them for a threesome.
Series Page
Raw Chapter Link (Pages 467-471)
Rating: 2
Karin and Harumi briefly kiss each other before Harumi is taken to be raped by a group of men.
Series Page
Chapter Link
Rating: 3
Panty and Stocking very briefly have lesbian sex with each other. (No Male Scene)
Afterwards, Panty has lesbian sex with a native tribal leader. (Male Joins Scene)
Tagging this as Male Joins because immediately after this scene, Panty has sex with a horse.
Series Page
Rating: 4
Mina and Huijoo are shown having lesbian sex with each other, but they’re eventually caught by the MC.
The MC then joins them for a threesome.
Series Page
Raw Chapter Link
Rating: 4
Motoko seduces and has lesbian sex with Saori in front of the MC before he eventually joins them for a threesome.
Series Page
Video Link (Rule34 Video)
Length: Long
Stays Yuri: Male Joins
Rating: 4
During the harem route and after all both girls are hypnotized, Sakura seduces and has lesbian sex with Megumu.
Eventually the MC shows up and joins them for a threesome.