Bloomsweet and keraji may be closely related.
Bloomsweet (believed to be the Japanese variety 'kinkoji' ) may likely be a kunenbo x buntan (pomelo) cross, while genetic studies suggest keraji resulted from repeated kunenbo backcrossing with some original sour variety. Satsuma also came about from a kishu x kunenbo cross.
Kunenbo is like a medium-large tangor-like mandarin, with a fairly strong distinctive aroma. (name translates as "nine year mother")