I started watching DBZ when I was just a wee lad, and the idea of shipping adults was still pretty foreign and kind of weird to me. I let B/V slide, under the premise that it was canon, and hey why the heck not.
Then I got older. My childhood memories slipped by the wayside, but I soon rediscovered them in a violent fit of nostalgia. More than a few smutty fanfics were read. And while my love for Gohan/Videl remained true, my passion for Bulma/Vegeta came to fruition.
Two incredibly stubborn, hard-headed individuals. A loyal, inquisitive genius human, and an egotistical warrior Saiyan prince. It seems natural that their friction would generate some degree of lust, which I have no doubt that that was the basis of their relationship initially, but over time they grew to care for each other more and more.
And eventually, Bulma would cry for the man who once fought against her friends, and Vegeta would sacrifice himself in a last ditch attempt to protect his family. They’ve come so far.