[2] On an episode of the MBC entertainment program Three Wheels, aired on May 21st 2013, Hyolyn and Bora explained that "19 represents nineteen, expressing the emotions of the boundary between girlhood and womanhood at the age of 19.

[5] The lead single of the same name ascended to the top of the Billboard Korea K-Pop Hot 100 chart.

[9] In an interview with fashion magazine Arena Homme +, Bora mentioned that making the decision to be a part of the duo has brought her a sense of stability.

Afterwards, Hyolyn sincerely stated that both of them want to convey the image and message that they have drawn and refined based on their genuine feelings and thoughts to those who have been patiently waiting for the past 11 years.

The teaser features a real-life silhouette of the duo against a red background, accompanied by the title "No More (Ma Boy)" written at the top.