POINT 1
In the Furiiza Saga, Furiiza had just dealt Bejiita the final blow. After the prince dies he comes back as a ghost to give Gokuu that last bit of coaching.

"You are the only one who can defeat him! you have the power!"

Bejiita was completely naked this entire time. (He's a ghost what does he need w/ clothes!) Gokuu didn't really look like he was listening he just seemed extremely shocked. I wonder why.

POINT 2
There's even more evidence in the Vegetto saga. While fighting Buu they did all of these perfectly coordinated team attack moves like Goten and Torankusu. In one "attack" Gokuu presses himself to Bejiita as close as possible. I got the impression he was trying to fuse with him again. Being that close was really not at all necessary for the attack. Then after Buu was temporarily blown to bits, Gokuu didn't move away:

Bejiita: "How long are you gonna squeeze yourself against me?! We have to destroy the remains of Buu!

Gokuu: "OH! Oh yea!"

I guess Gokuu's mind was somewhere else at the time.

POINT 3
Another way we know of their attachment to each other is how they always watch each other's backs. It's odd for someone who seems to want Gokuu dead, Bejiita saves Gokuu from the brink of death time and time again.

1) He saves him during the metal Kuuraa fight when he had the upper hand
2) He saves Kakarotto in movie 12 when he was badly beaten and Janemba was about to cut him in half.
3) During the Android Saga he saves Gokuu yet again from android 19 when his heart condition made him too weak to fight back. He's a bit rough about it (i.e. kicking him out of the way) but he does save him.

POINT 4
During the tournament saga, Bejiita was furious whenever Gokuu paid even the slightest bit of attention to anyone but him. He was even angrier when Gokuu left to go help Kai oo shin.

Bejiita: Look at Kakarotto sizing up his enemy....it's ME he should be worried about!

Bejiita: I only joined this stupid competition to so I could fight you!! If you're gonna leave make sure you COME BACK!!

I guess Gokuu does have this nasty habit of disappearing off the face of the earth. But what Gokuu said was even worse.

Gokuu: Alright! I promise to put you at the top of my 'things to do list' when I come back. Ok?

POINT 5
Bejiita just wouldn't let Gokuu out of his sight for a minute. He had no interest in Kai oo shin's problems and only went to keep his eye on Gokuu. He followed him everywhere.

POINT 6
During the tournament saga Goten had just lost to Trunks and Bejiita comes over giving him encouragement.

Don't worry Kakarotto your son always has next year. Then he puts his hand on his shoulder. Gokuu looked really surprised and kind of uncomfortable but really happy at the same time. I'm not sure what Bejiita really said since Cartoon Network has a habit of changing dubious lines. Now Gokuu usually seems so comfortable with himself, his body and being touched. Well he HAS been seen strutting around naked a number of times in the show. But it just seems odd that he would react that way to just being touched on the shoulder. Maybe it's because Jiita's doing the touching.

POINT 7
Bejiita actually risks his life for Gokuu very often. When they were fighting Buu, Gokuu needed time to gather strength. So Bejiita went to fight Buu even though he knew he would lose. He also knew if he died now he could never be brought back. But he did it anyway

POINT 8
Gokuu had finally made the spirit bomb and was ready to chuck it at Buu. But Bejiita was in the way. He'd been beaten really badly and couldn't move an inch. Gokuu begged Bejiita to move but he didn't.

Gokuu: Be..Bejiita, hurry up and move!!!

Bejiita: I can't!! Damn it! Just forget about me!! DO IT!

Gokuu: But...Bejiita

This went on for several minutes. He really didn't throw it even though the fate of the universe rested on his shoulders. He only threw it when Satan came and picked Bejiita up and ran while fat (glandular) Buu made a distraction.

POINT 9
As we know, Gokuu and Bejiita fight each other more than anything. Goten made an interesting observation about fighting one day.

Goten: I guess sometimes fighting and that kissy kissy stuff DO mix huh?

POINT 10
In the first episode of the Vegetto saga Gokuu and Bejiita were forced to use the Potara earrings to fuse. As the fuse, they are surrounded by blue light and are pulled chest first towards each other by some unseen force. All the while Gokuu had this big smile on his face as they are pulled together. It's probably the oddest way to fuse I've ever seen.