Wally and Kuki are likely characters in a particular fictional universe. They could be from a TV show, a video game, or a comic. Without more context, it's hard to say exactly who they are, but they are the focus of the fanfiction, which means fans are interested in exploring their relationship, be it friendship, romance, or some other kind of connection.
Brendan and Wally fanfiction often explores their relationship in unique ways. It could involve their adventures together in the Pokémon world. Maybe it shows how they support each other during their Pokémon training journey, like how they exchange tips on catching rare Pokémon or training strategies for battles.
Wally West's speed in the comics is off the charts. He can move at velocities that surpass the limits of normal comprehension. His powers allow him to zip around and perform feats that seem impossible to others.
In certain comic book runs, a black Wally West has made appearances. This character variant has added diversity and new story possibilities to the comics.
Wally West became the Flash after Barry Allen. His origin involves being the nephew of Iris West. He gained his super - speed powers in a similar way to Barry, through a chemical accident in a lab. This accident exposed him to the same forces that gave Barry his powers, and thus he became Kid Flash first and later the Flash.