Digital's four brain cells reenacting the Gaijin 4koma.
...Come to think of it, the real-life horse is American too. No mention of it in his umagirl counterpart though, unlike Grass/El/Taiki/Hishiama/Akebono/Pearl. I guess Digital already has too many character traits going for her.
(Though from a Western perspective it would merge well; weeb otaku and plain otaku go hand-in-hand.)
Pegasus's RL counterpart is also American, but so far there's no reference to it in his umagirl counterpart either.