How about "Koishi'sgirlfriend"?Must be nice for you, Koishi. Your name is pretty uncommon.Well then you should just change your name to something else, Kokoro-chan.Is it?Pleased to meet you, Hata no Koishi'sgirlfriend-chan!Don't be sillyExamples of other Kokoros:
-Kokoro Tsurumaki from Band Dream!
-Kokoro Yotsuba from Kamisama Minarai
-Kokoro from Dead or Alive
-Kokoro from Kokoro Toshokan
-Kokoro Kusunoki from Kuromajo-san ga Tooru!!
and so on