Sovian (uke) is confined and trained by Cyril, a human traffickar who is set on selling Sovian off as a 'dog'. Sovian is eventually 'rescued' by Zerkin though.
Ch. 30 - Ch. 37
Uke to seme: master. Seme to uke: 'dog'
⛓ Private train carriage closed off by iron bars
Collar and attempted piercing of nipples
Seme plans on selling uke off
Uke got more than he bargained for and is mentally broken by a presumed serial killer who decides to keep him as a pet (bad end?).
Ch. 3
⛓ Basement with lockable door
Collar and chains
Mind break and Stockholm syndrome
Uke accepts his imprisonment
The uke (unnamed) is caught by a shady organisation when trying to rescue his senior. The seme, a higher up, takes a liking to the uke and decides to keep him and train him to be his 'dog'.
⛓ Chained up and to be kept as a dog by the end
Collar and seme mentions piercing ukes nipples later
Becomes the semes 'pet dog'
Cha Junseo (seme) is a twisted man due to his upbringing and a traumatic dog attack inside a (Tosa) dog cage, caused in part by his childhood crush and obsession Baek Doah (uke) locking him in with said dog. Cha Junseo is now set on turning Baek Doah into his pet and keeping him locked up in a cage just like a Tosa dog.
⛓Cage
Dog collar
Uke to seme: master
Mind break and total submission
Uke accepts being kept in a cage forever
Ren (uke) is abducted and played with relentlessly by man deaply involved in the criminal underworld called Itsuki. He became obsessed with Ren after Ren attempted to treat him after he was wounded in a fight. His face having been seen by Ren that time, he has no choice but to make Ren disappear. But instead of killing him, Itsuki decides to keep Ren as his pet in twisted expression of gratitude.
⛓ Confined to a mansion
Partial mind-break
No escape
by Yona
Kyo (uke) wakes up nude and shackled. A mysterious man introduces himself as his master and informs Kyo that he is tasked with turning Kyo into a sex slave for personal use, fit to be sold in an upcoming black market auction.
Uke to seme: master. Uke about self: sex slave
⛓ Basement
Choker and chains
Presented at auction
Complete mind break
[SPOILER] Turns out his new owner is his stepdad...
by Yona
Part 2 of Indecent Gallery by Yona. Not my cup of tea because of the group sex. We do finally get to see Kyo's master's face though; pretty much an aged up version of Kyo's trainer in part 1.
p. 48 - 54: part not involving group sex.
Dog collar
Kyo refers to him as 'daddy' during most of the thing, which might be a turn off for some readers ([SPOILER for part 1] especially because of the not-technically-incest trope...).
by Haguruma
Shiro (uke) is summoned to another world by a group of wizards by error. Making the best of their mistake the group decides to sell Shiro to a slave trader, who subsequently auctions Shiro off to a handsome demi-human aristocrat named Lecter, who intends to keep Shiro as his pet.
Collar
Sold at a slave market
Temporary mind break during sex (heart eyes)
Seme intends to keep uke as a pet, forever
Escape Room Game