Valmiki Ramayana Aranya Kanda Sarga 38 Shloka 24
Original Shlokaक्रीडारतिविधिज्ञानां समाजोत्सवशालिनाम्। रक्षसां चैव सन्तापमनर्थं चाहरिष्यसि।।3.38.24।।
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क्रीडारतिविधिज्ञानाम् of those who know lovesport, समाजोत्सवशालिनाम् of those who celebrate community festivals, रक्षसां चैव of demons too, सन्तापम् grief, अनर्थं च disaster, आहरिष्यसि you will bring.
You will bring grief and disaster into the lives of demons who are sporting in love and who are in the habit of celebrating community festivals with joy.