The reality television star, whose sister Kim recently announced her engagement to Kris Humphries, used the social microblogging website to hint that Rihanna should be his date to the wedding.
Rihanna initially tweeted about her night in, writing: "Ugh! DUH!!! Popcorn and remote in hand," to which Rob replied: "I can make this right here happen."
The singer wrote back to him: "It's past your bedtime," and he answered: "Goodness. Child please. Hush lil baby don't say a word." He later continued the flirt, writing: "You can put me to bed," around the same time he wrote: "I need a date for my Sis @KimKardashian WEDDING! (sic)"
Rob recently admitted that he is not sure if Kim will actually make it down the aisle with Humphries. He said: "I just don't feel confident because Kim has... been through a lot of relationships and she always gets hurt or never finds the right dude."
A friend of Kim, however, has said that the wedding is going ahead and the star plans to make it more "massive" than the royal wedding. At the weekend, Kim also revealed that she hopes to start a family with Humphries this year.
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