Now the final OVA is probably the best completed of the OVAs, called “Shiton Doubutsuki”. One of the criticisms of the Golden Kamuy anime compared to the manga is how it cuts out the world-building and Ainu culture elements, which are a core piece of the manga. This OVA is likely the first time that aspect was nailed.
As we are aware, there are tons of stories of humans and gods being married. For Golden Kamuy, Ainu refer to them as Kamuy. As Asirpa points out in those stories, the Kamuy has a human form. It is because humans can only marry humans. Kamuy/animals can only marry Kamuy/animals. It is an ingrained part of their culture.
One of the more interesting parts of the OVA is in the aftermath Sugimoto feels bad for Anehata. Of course, everything that he did to those animals and then proceeded to kill them, Asirpa has no sympathy for him. As killing them would imply what he did to those animals was wrong. Her reasoning is very on point. It is very interesting to see the switch of roles where we see Asirpa feeling bad for the prison convicts and Sugimoto knowing they are awful people.
So should you watch this final OVA? If you love the cast, comedy, and the Ainu culture elements, then yes. This OVA did cover chapters 108-113 of the manga, but the beginning of the episode is actually what happens at the end of episode 18. As the end of episode 18 is anime original. If you only care for the main story, it is skippable since the only notable thing to remember is Sugimoto collecting another skin. The anime doesn’t keep track of the skins like the manga doesn’t, so that might not be as big of a deal. Also, to add, the Golden Kamuy experience is more about the adventure and the end goal with how it is written.