"Pupil of Kunisada. At first he signed his prints Baido Kunimasa III or Kunimasa; in 1846 he married his master's daughter, taking the names Kunisada II, Kochoro, and Ichijusai; from about 1870, after Kunisada's death, he used the name Toyokuni III (actually, IV)." --'Images from the Floating World' by Richard Lane
Note the Genji-mon (Genji crest) for the 36th chapter (Kashiwagi) of the Tale of Genji in upper left red clam shell cartouche as well as domestic items including hibachi, candle lamps, bonsai tree, etc.
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