光井愛佳 (Mitsui Aika) is a former Japanese singer. She was an 8th generation member of Morning Musume. under Hello! Project. After suffering a leg fracture in 2011, she was unable to keep up with a new dance-oriented Morning Musume., and graduated alongside Niigaki Risa in May 2012. However, she stayed within Hello! Project and was the first Morning Musume. graduate to do so since 2007. She was listed as a soloist, but she never released any music due to her going on hiatus twice since 2013 to study English in New Zealand. While on her second hiatus in November 2018, Mitsui decided to graduate from Hello! Project and retire from the entertainment industry.