Menma and Hinata are part of an alternative universe created by Obito or Tobi during his time when he wanted Naruto to suffer. Naruto had traveled to an alternative universe where he met Menma and Hinata who were, at that time, in a relationship.
You may know these from the movie Road to Ninja, the image you see here I believe to be quite fantastic. Both Menma and Hinata look crazy strong seem to be a good representation of what they could be. Menma is SunwardLight while Hinata is Zerocchin. If you like their work here be sure to check them out, otherwise be sure to share the page else where!