Good news: no dogs, whether people in costumes or actual dogs, die. Bad news: the movie's ending will make you wish the costumed dog(s) died as it's honestly a more preferable outcome than being abused indefinitely.
Not quite the same, but Frank and Sigrid both make plans to kill Christian in his sleep so they can escape. It's arguably self-defense, especially in this context, but may still be triggering in a similar vein.
Major trigger warning for DV, as it is ultimately a major theme of the movie. Frank initially appears to be a consenting partner in a BDSM dynamic, but it's later revealed that Christian forced him into that position. Christian also behaves abusively to Sigrid as the movie goes on, such as taking her phone away, keeping her isolated, attempting to force sexual contact, and verbally berating her. Frank and Sigrid even contemplate killing Christian in his sleep in order to escape, which doesn't work out. The climax has Christian torture Frank in a way that evokes BDSM but is clearly abusive in context. The movie ends unhappily, with not only Frank still imprisoned and Sigrid herself becoming a 'puppy,' but also what appears to be Sigrid's and Christian's child also acting out the 'dog' role.
The final few seconds implies there is and will continue to be. spoiler: it shows a toddler being taken out of a dog crate and being told to “come” to eat out of a dog bowl
this movie is about an man who has a “roommate” in a dog suit. the man dressed as the dog is abused but no actual dogs or other animals were in this movie
Frank and Christian's dynamic is revealed to be nonconsensual on Frank's end, as a scene has him break character and beg Sigrid to leave once they're alone together. It's unclear if Christian and Frank are having sex, but there are definite BDSM undertones to the abuse, especially during the torture scene in the climax. Christian also tries to force sex on Sigrid as she plans to make her escape. The last scene might also be a trigger, as not only has Sigrid joined Frank as one of Christian's 'puppies,' but there's a child in the same position, implicitly Sigrid's and Christian's. The child may have been conceived through SA offscreen, though an early sex scene might have also been where he was conceived. Given that Christian is also treating the baby like a dog, he may be sexually abusing him as well.
A baby appears in the last shot of the movie in a context that may be upsetting, as it implies forced pregnancy and/or sexual assault, and maybe incestuous pedophilia of the child in question.
Subtle, but Christian tries to explain Frank's apparent desire to be a dog by explaining that he's had 'a tough life,' which implies he's using puppyplay as a coping mechanism for past trauma. However, this is proven to be wrong, as once he manages to be alone with Sigrid he starts begging for them to escape, revealing that it's nonconsensual. While it's never clarified whether Frank does have pre-existing trauma, the fact that Christian tries to pass it off as consensual using his alleged trauma as an explanation for his behavior could be considered ableist.
Puppyplay, a variant where one of the participants acts out the role of a dog, is a major part of this movie's premise. Frank appears to be in a 24/7 puppyplay dynamic with Christian. While it initially appears to be something mutually agreed upon, it's later revealed that it's not safe, sane, and absolutely not consensual, as Frank is forced into that position. The torture scene during the climax is evocative of BDSM 'punishments' but is, again, nonconsensual and clearly distressing to the sub. The movie ends with two more people-- a woman and a young child-- forced into the same position.
Maybe? The last shot of the movie reveals that Christian now has an infant/toddler-age son, implicitly conceived with Sigrid, who he is also training to be a puppy. It's unclear if any sexual contact occurred in context, but the BDSM themes of the abuse make it unnerving. At the very least, it's definitely abusive.
The movie ends on a depressing note. Not only are Sigrid and Frank unable to escape, but Sigrid now lives as one of Christian's 'puppies' alongside Frank. To make matters worse, the last shot reveals that Christian now has a infant son, implicitly fathered with Sigrid, who he is also treating like a dog in the same way.