He couldn't become a pet dog. Because he was the proud Kamuy, Holokeu Kamuy2

"Can you hear it, Sugimoto-san? It's an unusual sound."
"..."
"It's a howl thicker and longer than that of a dog. It belongs to a wolf."
"I've seen a big white wolf twice, protecting Asirpa-san. What's the relationship?"
"I see... so that howl was indeed from Retar."
"That wolf was found when Asirpa and her father went hunting in the mountains and stumbled upon it being attacked by a bear. It looked like a small snowball, so they named it Retar, meaning 'white'."
"They were always together. Even after her father was killed, Asirpa went to the mountains with Retar alone. But their worlds of survival were different. That day, a howl like tonight's reached Asirpa and them on the wind."
"It's a howl... Retar... This is yours... No, don't listen! You can't!"
Whine
"No, don't. Wait! Stop! Go back to the hut, Retar!"
...He couldn't become a pet dog. Because he was the proud Kamuy, Retar...
"Retar! Don't go! Come back, Retar. Are you leaving me alone too? Waaaaah. Don't go, Retar... Achaa (Dad)."
It's the story of Asirpa and the proud Ezō Wolf, Retar, from "Golden Kamuy".
Retar (Golden Kamuy) 

The Japanese Wolf once inhabited the mountains and wilderness of Honshu, Shikoku, and Kyushu in Japan.
The Japanese Wolf, a subspecies of the Gray Wolf, was relatively small, with a body length of about 1 meter and a shoulder height of about 55 cm.
Much about its ecology remains unknown, but it is believed, based on old literature and folklore, to have formed packs of 2 to 10 individuals, nesting in caves in the foothills and spreading across fields of susuki grass.
Its main prey was deer, but occasionally, it would descend into human settlements and attack livestock.

As you know, unfortunately, the Japanese Wolf, like many other species, was driven to extinction by human activity.
Several factors are thought to have contributed to its extinction.
In Japan, where agriculture was widespread, wolves, which helped control deer and wild boar that damaged crops, were regarded as protective deities. In fact, there are shrines dedicated to wolves.
However, with the introduction of rabies from overseas, the Japanese Wolf came to be seen as a dangerous predator. At that time, rifles were becoming widespread, and wolves became targets. Additionally, rifles were also used for hunting deer, further reducing the wolves' food supply.
Furthermore, the ongoing development since the Meiji era led to the loss of the Japanese Wolf's natural habitat. The spread of canine distemper, an infectious disease introduced by foreign dogs, also weakened the wolves.

While none of these factors alone caused the extinction, the combination of these factors led to the demise of the Japanese Wolf, which once ruled the apex of Japan's ecosystem.
The last confirmed Japanese Wolf was a young male caught in a trap set by humans in Nara Prefecture in 1905.

Domesticated dogs, known for their obedience and intelligence, have a long history as human companions. They also serve as working dogs, such as police dogs and guide dogs.
Currently, there are about 400 recognized dog breeds.
In 2017, a study analyzing the DNA of 1,346 dogs from 161 breeds was reported. According to this study, the breed genetically closest to the wolf was the Basenji, native to Africa. Following the Basenji, breeds such as the Shiba Inu and Akita, classified as "Asian spitz types," were considered closely related to the wolf.
These breeds, also known as "ancient dogs," are genetically distinct from Western dogs. Surprisingly, breeds like the German Shepherd, which visually resemble wolves, are more distantly related.
Generally, the farther a breed is genetically from the wolf, the shorter its muzzle tends to be. This shortened muzzle is also a characteristic of wolf puppies. It's interpreted as a retention of juvenile traits during the domestication process, as being cute and dependent likely increased a dog's chances of survival.