Denshi Jisho — Online Japanese dictionary

書斎 しょさい study; library; den; home office; reading room
Common word, Noun 
書斎に籠る しょさいにこもる to shut oneself up in one's study
Expression, Godan verb with ru ending 
書斎にこもる しょさいにこもる to shut oneself up in one's study
Expression, Godan verb with ru ending 
書斎に籠もる しょさいにこもる to shut oneself up in one's study
Expression, Godan verb with ru ending 

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