Sorry bro, terrible picture and explanation of the location. Unless the hose was cut shorter than the original there's a not a lot of choices. Possibly post a picture that gives a reference to where the hose is.

 

So I think I might just be dumb. I went out after my wife went to bed and it looks like that hose might just be a spare house. It seems to have clamps n both ends and doesn't actually connect to anything.

 

What year? Which engine? Is this under the rear of the car? If so, probably an EVAP hose.

 

There is no such thing as an extra hose. If Toyota put it in there, then it has or had a purpose. What this likely means is that somebody has been there before. That hose may have been replaced and forgotten under the hood. Or somebody officially did an incomplete repair. I see two ends of hoses each with hose clamps a little low and left of center in the picture. I'd look for evidence of a broken connecting nipple between the two. That's all I can really offer for what I can see.

 

Ive seen a couple hoses in Toyota unattached at one end, like a/c drain or evap hose, but Toyota wouldnt put a hose clamp on the end. Something is missing there.

 

If your car has a sunroof, it may be a drain coming from the factory drain. My wife's 2013 has the world's worst drain so I went in and added a hose that goes out through the floorboard and truly drains under the car. Sad that an idiot like me had to do something an "engineer" failed to do.

 

What is this part encircled with the red pen? Its cleanliness compared to the other parts connected to it suggests that it was replaced. Perhaps is is the wrong variation of that part and a port was either moved elsewhere or was not included on this variation.

 

hoses with one end:

trans breather
ac drain
cowl drain
diff breather

things like that.

it could be a valve cover breather that was never connected. it could be a trans or diff breather that someone extended.
it looks short, so just move it around and see if it reaches a fitting that dosent have a hose on it. lol

if its connected to something on the other end, let us know what its connected to.

 

hoses with one end:

trans breather
ac drain
cowl drain
diff breather

things like that.

it could be a valve cover breather that was never connected. it could be a trans or diff breather that someone extended.
it looks short, so just move it around and see if it reaches a fitting that dosent have a hose on it. lol

if its connected to something on the other end, let us know what its connected to.

What is that just below, to the left in the picture? Looks like a broken connector nipple with a clamp still on it (maybe). There may be something similar at the other end of your hose in question?