This happened 2 years ago (2009).
It happened in Mill Hill Block St. Joe Kch. around 5 something, almost 6 to be exact.
This story was from my friends, let's call them K and A.
Ah, before that, let me tell you that we loveee to sing. We sing everywhere even outside the class. K and A were selected for the school choir team.
So that evening, K forgot her tumbler in the class. K asked A to teman her to go upstairs together. K actually felt something was wrong. But, she just ignored it. So they sang on their way to our class. Our class is on the 3rd floor. Same floor with Counselling Room. At that moment, no one was there. The counselling room was closed too. On the way down, they sang again lol

. This time they sang 'Muhibbah' song. One of the choir songs.
"Muhiiiiibbah muhiiiibbahh itulah amalan kita semuaaa" Then suddenly, they heard a voice out of nowhere, sing along with them. Veryyy sayuuu. K and A just ignored it but their step were getting faster and faster.
-The End-
Its time to sleep, buenos noche!