Jadesprite is Jade’s dreamself and she was prototyped with Bec so when Jade died on her Quest Bed, Jadesprite went godtier and she retained some dog features including his ears. 

He doesn’t like to label his sexuality but we know from his post-trickster convo with Jane that’s he’s only into dudes.

She is a Seer of Mind and thus could See brain-ghost-dirk, a figment of Jake’s Mind

So for in comic characters moving at normal speed (ex. Spades Slick, Ms.Paint, etc) the battleship took only 3 seconds to move between the walls but to those on the ship it lasted 3 years because they were moving so fast through space that they moved through time at a rate significantly slower than usual. The concept applied to this is a real thing called Time Dilation, I recommend you look into that for a more thorough explanation.

For trolls, they conceal their wings and change out of the outfit. Humans can just change their clothes. 

Brain ghost Dirk is a projection in Jake’s mind that only he can see. He’s a startlingly close approximation of Dirk’s mannerisms and behavior based on Jake’s intimate knowledge of him. Jake can actually bring him into existence once he tapped his full Page powers.

The Alpha kids’ Jack Noir looked into Lil Cal’s eyes and was possessed by Caliborn. He then stabbed out his eyes and replaced them with Lil Cal’s and cut off one leg and replaced it with a golden spike.

Yes, Dersites and Prospitians can experience the full range of quadrants. 

They are in some kind of relationship but it has not been specified as to what kind it is.

They do have a bulge, it being a tentacle though is fanon.