This mecha paper model is Candy Heart (Candy Person 105), a Candy Person that first made his appearance in the episode "Slumber Party Panic" as a candy zombie, but was brought back to normal and made a brief cameo in "Too Young", based on the American animated television series Adventure Time, the papercraft is created by WebDude.
He also made an appearance in "Susan Strong," dressed as a ghost. He later appeared in "From Bad to Worse," becoming a zombie for the second time but is once again cured. Zombified Candy Heart guy makes an appearance in Level Three of Rhythm Heroes.
He is a blue candy sugar heart with the words "Tug Me" on him, which is ironic since candy hearts usually sport positive phrases like "Hug me." When he is a zombie, the letters spell out "Ug me," due to the bite removing the T. [Source: wikia]
You can download the papercraft template here: Adventure Time - Candy Heart (Candy Person 105) Free Papercraft Download