It’s the ending song of the anime ‘あの夏で待ってる’ (Ano Natsu de Matteru), titled Vidro Moyou, sung by Yanagi Nagi. Credits to rurouni1928 for the original tab, I modified the song a bit to match my fingering position. You can download the original tab here: http://firestorage.jp/download/83fc7b83d5ae4051ddaca62c100274ff7cc11a26
