Monday, December 9, 2019 
LOONA has dropped a big hit to their fans.
At midnight on December 10 KST, the group's agency Blockberry Creative released an unannounced image teaser for '365,' puzzling fans with exactly what kind of release it is teasing.
In the image, there is a glowing moon with the numbers 3, 6, and 5 layered atop one another in pink, yellow, and blue. The caption for the image simply reads, "Through the heart of the 365-day moon."
Meanwhile, '365' will be unveiled on December 13 at 6 PM KST, a day before their December 14 'Premier Greeting' event at Seoul's YES24 Live Hall.
What do you think '365' will be?
365일 달의 마음으로
— 이달의 소녀(LOOΠΔ) (@loonatheworld) December 9, 2019
2019. 12. 13 PM06:00 (KST)#이달의소녀 #LOONA #365 pic.twitter.com/adhbtRBmJB
6
Finally! these girls are amazing! that Butterfly comeback was beautiful, I can't wait to see what they'll bring next! :D