Ruggie has at least two comments about other people being friends, but the one time he comments on having friends on his own was possibly meant to be sarcastic (he talks about getting gifts for friends for their birthdays for the purpose of getting presents in return).
Ruggie has a line about giving the prefect a “friend discount,” but as it is part of a pitch to sell his services this is possibly also insincere.
When a stranger during Port Fest refers to Leona and Jack as his school friends he does not deny it, but he was also being accused of stealing a wallet at the time.
Silver mentions seeing friends of Ruggie in the foothill town, but Ruggie is not there to confirm or deny.
When Rook comments on Ruggie fostering friendships through club activities Ruggie responds, “I mean, I wouldn’t say we’re close, exactly.”
Twisted Wonderland Reference Note 