Hachi

From Wiki Ippo

Hachi is the pet dog of Nekota Ginpachi. He is possibly a mix between an Akita and an Alaskan Malamute (according to Morikawa himself). He made his appearances in Tokyo with Nekota when watching the matches of the Kamogawa boxers. But Nekota could not enter Hachi because pets are not allowed in Kourakuen Hall. So, in Nekota's next return to Tokyo, he hid Hachi in a large sack.

When Makunouchi Ippo finally beat Sendou Takeshi, Hachi went down the hall and into the ring just in time to be captured in Ippo's victory pose/picture.

Hachi is the father of Wanpo (Ippo's dog) which Nekota gave to Ippo as a gift.