Charak Samhita
अतिबालो ह्यसम्पूर्णसर्वधातुः स्त्रियं व्रजन्। उपशुष्येत सहसा तडागमिव काजलम् ॥४१॥
If a young boy of very tender age whose body elements are not yet fully formed, enters in to sex act with a woman, his body gets dried up like a pond having very little water.
english translation
atibAlo hyasampUrNasarvadhAtuH striyaM vrajan। upazuSyeta sahasA taDAgamiva kAjalam ॥41॥
hk transliteration by Sanscript