InOut's users press a rectangular section in the top of the timepiece to reveal a second hidden clock, which can be used to display the alarm time.
The alarm screen can then be hidden and deactivated when the pop-up element is pressed again.
"InOut is inspired by the frustration of setting the alarm when going to sleep and not knowing if it is set properly," said Serrano, who previously designed a portable speaker shaped like the computer sound icon for French brand Lexon.
"The alarm time is clearly indicated not only graphically but physically," he added.
The clock features oversized plus and minus buttons with engraved symbols at the back of the main device and the alarm element.
These are included to allow owners to set the time without having to turn the clock around.
The clock comes in white, red, blue green, blue, grey and lime green versions, and features a rectangular screen display with large digital numbers.
His InOut clock is on display at the Maison&Objet trade fair, which is taking place at Paris' Nord Villepinte exhibition centre from 22 to 26 January 2016.
Another alarm clock released by Lexon requires the owner to flip it over to turn it on or off.
Other unconventional clocks include Zelf Koelman's design that uses ferrofluid and electromagnets to display the time, and Breaded Escalope's touch-responsive clock that uses shadows to tell the time when a finger is placed on its face.