Describe Dr. Jekyll's fascination with Mr. Hyde's lifestyle in The Strange Case of Dr. Jekyll and Mr. Hyde.

Before Dr. Jekyll created the drug that would separate the good and evil sides of man, he actually lived a dual life. He pretended to be an upright person, but he occasionally "laid aside restraint and plunged in shame." According to Jekyll's letter, when Jekyll became Hyde, he was aware of Hyde's experiences and remembered them when he returned to his Jekyll persona. On the other hand, Hyde was only vaguely aware of Jekyll when Hyde was in the ascendancy.
Stevenson is quite abstract about the dissipation Hyde participated in—other than to describe the violence against the child and the murder of Sir Danvers Carew. Jekyll's letter states that Jekyll, both while in the form of Hyde and after returning to the form of Jekyll, relished Hyde's "heady recklessness" and his livelier spirit. What appealed to Jekyll was the freedom Hyde possessed; he lived only for his personal pleasures and wasn't encumbered by rules, conscience, or other people's expectations for him.
At one point, Jekyll had to make a choice which persona to take as his own. He begrudgingly chose the persona of the "elderly and discontented doctor," and said goodbye to the "liberty, the comparative youth, the light step, leaping impulses, and secret pleasures that I had enjoyed in the disguise of Hyde." The fact that he didn't destroy Hyde's clothes or give up Hyde's house in Soho revealed his ambivalence; he was fascinated by the life Hyde led and wasn't fully convinced he wanted to abandon it.