I also stumbled upon the same Numberphile video! Puzzle & Dragons is available in English and has a small following in North America. (There was also a version of the app in Europe but it got shut down a few years back.) Most of the English-speaking community is on Reddit and Discord now. As for why there are several glitch tokens related to the game: My guess is that it's pretty similar to what happened with the r/counting subreddit. P&D related terms would probably only come up within r/puzzleanddragons and the Discord server. There used to be several large English websites about the game, namely puzzledragonx and padforum, but those both disappeared in the last few years. Any information that you would find about P&D outside of r/puzzleanddragons is likely many years out of date, e.g., the wiki that was found in the Twitter thread.
Leilan is interesting one. She and her siblings are based of off four mythological Chinese constellations (white tiger > Haku, black tortoise > Meimei, blue dragon > Karin, red bird > Leilan; Sakuya is a special case and is presumably related to the qilin). A user of r/puzzleanddragons suggested that Leilan might be a weird token because she was referred to as "Suzaku" early in the game's history. Additionally, the given names of the other four goddesses are likely to appear in other contexts, e.g., Haku isn't an uncommon name. It surprises me that parts of Tsukuyomi and Amaterasu are weird tokens because those names can be found in many different places.
I also stumbled upon the same Numberphile video! Puzzle & Dragons is available in English and has a small following in North America. (There was also a version of the app in Europe but it got shut down a few years back.) Most of the English-speaking community is on Reddit and Discord now. As for why there are several glitch tokens related to the game: My guess is that it's pretty similar to what happened with the r/counting subreddit. P&D related terms would probably only come up within r/puzzleanddragons and the Discord server. There used to be several large English websites about the game, namely puzzledragonx and padforum, but those both disappeared in the last few years. Any information that you would find about P&D outside of r/puzzleanddragons is likely many years out of date, e.g., the wiki that was found in the Twitter thread.
Leilan is interesting one. She and her siblings are based of off four mythological Chinese constellations (white tiger > Haku, black tortoise > Meimei, blue dragon > Karin, red bird > Leilan; Sakuya is a special case and is presumably related to the qilin). A user of r/puzzleanddragons suggested that Leilan might be a weird token because she was referred to as "Suzaku" early in the game's history. Additionally, the given names of the other four goddesses are likely to appear in other contexts, e.g., Haku isn't an uncommon name. It surprises me that parts of Tsukuyomi and Amaterasu are weird tokens because those names can be found in many different places.