As reported by The Daily Mail, Lovato shared the above photo with her Instagram followers and made sure to clearly state the two are "best of friends." So, it doesn't seem like the beginning of a rekindled romance.
The two began dating back in 2010 but split in June of last year. Afterward, Lovato was romanticly linked to Luke Rockhold, a UFC fighter, before settling into a relationship with mixed martial arts fighter Guilherme ‘Bomba’ Vasconcelos.
Lovato and Bomba supposedly had a good relationship, with Lovato once saying in an interview, "I'm just having fun; you know? And my life is in a really good place right now. He makes me laugh," but they two split up recently.
While it looks like Lovato and Valderrama are just casually enjoying each others company, there's likely another reason they're spending time together.
The two actually have an animated film coming out soon that they perform in together.
It's titled Charming, and it's described as follows:
"The film explores the untold stories of Snow White, Cinderella, and Sleeping Beauty who discover that they are all engaged to the same Prince Charming. After a fairy spills a large amount of charm dust on Charming, Prince Charming, led by the heroine Lenore, a woman who is incapable of love, must go on an epic journey to find his true, true love."
Lovato provides the voice for Lenore, and Valderrama voices the title character, Charming.
While this is likely just a one-off, extenuating circumstance, perhaps working together will incite some unknown spark between to two of them. Only time will tell.