His name may be a reference to hares (more specifically, the Irish hare), a species similar to rabbits, or it might be a more specific reference to Peppy Hare, a character from the Star Fox series. His name could also be referencing the Chicago O'Hare International Airport, as his theme appears to be travel-oriented.
However, his Japanese name Santosu (Santos, in Portuguese), his catchphrase (amigo, meaning friend in Portuguese) and his house appears to be related to Brazil, since it is a Tropical country with many beaches.
O'Hare is a rabbit with brown fur and a tuft of orange hair, a green nose and green on the insides of his ears. He has orange teeth which can be seen when he opens his mouth. He also wears a yellow top hat with a black trim, making him one of the few villagers to wear headgear. His eyes are wide and black, and look somewhat stoic; hinting towards his cranky personality, (or smug in New Leaf). He initially wears a Blue Aloha Tee, or a blue Pineapple aloha shirt in New Horizons.
Below is a brief description of the cranky personality. For more information, click here.
Cranky villagers will usually appear in a grouchy or agitated mood and are more difficult to befriend than most other villager types. When talking to the player, cranky villagers tend to become angry if the player disagrees with them or refuses to do a favor. Like all cranky villagers, O'Hare will be invested in his hobby and will often challenge the player to various competitions. He will easily get along with jock, snooty and other cranky villagers, and occasionally lazy and normal villagers as well. However, he will find it hard to socialize with peppy villagers, as they will seem overstimulated or immature. O'Hare will also enjoy spreading rumors about other villagers.
Below is a brief description of the smug personality. For more information, click here.
Smug villagers are very polite, kind, and gentleman-like. As a smug villager, O'Hare will get along easily with other villagers. Smug villagers get along well with most villagers, their personality appearing to be a mix of the other personality types. As a smug villager he will stroke his ego from time to time, going on about how cool he is.
In New Leaf, his room has an Island theme, with items such as the Hammock, two Regal Benches, a Beach Parasol, a Lantern, a Canoe, and a Beach table. He plays K.K. Island on his Reel-to-Reel. He uses the Sea View and Tropical Floor as wallpaper and flooring.
In New Horizons, his room has again an Island theme, with two mini 'islands' formed by his Tropical rugs, in the middle of the sea made by his Ocean-horizon wall and Water flooring. One island contains a Beach Towel, some Coconut juice, a pair of Flip-flops, and a Cassette player, playing K.K. Island. The other island has a Cooler box, an Outdoorsy fishing rod, a Palm-tree lamp, and a watermelon Beach Ball on it. Sitting in the water are a Life ring, a Wave breaker, and one of Flick's models, the Great White Shark.
He is the only villager to still sport the Blue Aloha Shirt as of New Leaf.
As of New Horizons, the Blue Aloha Shirt is no longer a clothing item.
Him, T-Bone, Wart Jr., and Sue E. are the only four villagers with punctuation marks in their names.
He is possibly named after an Irish Hare.
As an islander, he has a favorite fruit and a fruit that he is allergic to. Feeding him the allergy fruit will reduce the likelihood of his dropping money bags. O'Hare is allergic to Peaches and loves Oranges.