Hikki has been tweeting up a storm over the past few days. Over forty tweets in the past three days from her official twitter account @utadahikaru.
She had mentioned that she was in Germany recently for the Rock im Park music festival in N?rnberg. The festival took place June 1st-3rd. She mentioned that she of course did not perform, but specifically went to see Metallica perform. She is now back in Asia .
Thanks to a tweet from Skrillex: "@utadahikaru follow people!!", Hikki has begun following others on twitter (other than her father and her staff). There are only a handful at the moment, but Skrillex, Junko the guitarist from her WILD LIFE concerts, Mika, and Conan O'Brien are among those that she is now following.
It is possible that Hikki and Skrillex recently met in Germany, as Skrillex was also at the Rock im Park festival as a performer.
 An assumption from the time of her good night tweet.