What caught the cast members' attention was the fact that the idol star consistently changed into different pairs of pajamas after each task, showing off his unique 'pajama fashion'.

Seeing this, the members commented in the studio, "That's a clear sign of aging," "He looks like an ajusshi (old man)."

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However, Taeyang refuted the remarks, saying, "Doesn't it look classic to you guys? Wearing pajamas like that is a must."

Afterward, he went out for a jog in, you guessed it, pajamas, taking his time while exercising in the neighborhood. The idol went through 4 different pairs of pajamas up until he finished showering, before he finally changed into more casual clothes to go out for a drive.

Watch clips from Taeyang's 'I Live Alone' debut above and below!