Really, never knew about Rio de Janeiro-maru or Santos-maru at all. ^^;
If you think I'm making this up, just Google it yourself!Operates with i-8 and Yura in the 5th Submarine Squadron and Southwest Area FleetHacchan, you speak GermanTa-da!Kancolle Trivia!Hacchan is international, so I've been fluently talking with her in her foreign language. There really was an Imperial Navy auxiliary transport ship named Rio de Janeiro MaruFrom 1941 to 1943 she served as an auxiliary submarine tender.