This past week, Studio Ghibli released four pieces of artwork from Castle in the Sky on their Twitter account for fans to use freely. This is the second time recently that the production company has released artwork for fans to use via its social media account. Both times the artwork has been released with the disclaimer that while fans can use it freely for their own use, they should not use it for anything inappropriate.Castle in the Sky is one of Studio Ghibli's older, but still beloved movies. It originally was released in 1986, and has been cited as highly influential for modern Japanese storytelling and anime. It also had a huge impact on the steampunk and dieselpunk genres even outside of Japan.RELATED: Incredible Studio Ghibli Experience Open for a Limited TimeThe images were released in a set of four, and can be used without risk of copyright infringement by anyone who wishes to use them. They all feature one of the movie's main characters. The first is Muska, reading すばらし (subarashi), or "wonderful." Then there is Pazu reading またね (matane), or "see you later" and Sheeta with simply "OK," a phrase used in both Japanese and English. Finally, there is Uncle Pomme reading ほう (hou), like a sigh.

A few weeks prior, Studio Ghibli posted an image of Calcifer from Howl's Moving Castle holding a blank sign board with a similar message that it could be used by fans for anything (as long as it was not inappropriate). Many fans responded by tweeting the image back to the studio with "thank you" or something similar on Calcifer's sign. Both the Howl's Moving Castle image and these latest ones from Castle in the Sky are likely meant to be used on social media.

In a world where it can be easy to be called out for copyright infringement online, it is nice to have some images given by an official studio that can be used without fear. It will be interesting to see exactly how fans around the world use these images, but likely they will find some creative uses for them and otaku can expect to see them popping up around the internet.

While Castle in the Sky is a highly influential movie and does have a lot of fans out there, it is an interesting choice for the photo set as it is not one of the most popular Studio Ghibli films. When it comes to popularity, Spirited Away, My Neighbor Totoro, and Kiki's Delivery Service often top the charts, and dominate the merchandise. However, none of these films have been used yet for photo sets.

What that could mean, though, is that these photo sets may be only the beginning. Both the images from Castle in the Sky and Howl's Moving Castle have been very different. There may be even more styles coming in the future, and hopefully continuing to feature more and more Studio Ghibli films. Keep an eye on their Twitter account in the coming weeks.

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