as youth —

her beloved, who is having mountain-like huge shoulder and who is proud like a bull —

one who is a youth with his shoulders similar to a mountain —

 a dark, young person came —

krishṇa who did not lose his youth (even after that) —

 being youthful —

 ever youthful emperumān —

 being ever youthful —

 the youthful one —

 youthful chakravarthith thirumagan —

 young —

who is incomparable —

 being a youth —