Where have I heard that - 'De-de deen' before? Is it a well known thing? I think it was in an anime where someone was presenting something.. maybe in yuru yuri or something..?
Edit - found it - it's used twice in ep 10 of Yuyushiki :)
(And not in any way referencing Love live) - it seems to be just like 'Ta da!'.
last edited at May 29, 2016 9:40PM