Interesting how a "Saiyan pride" thread became a "Saiyan sexuality" class. I approve.
While I don't doubt rape wasn't beyond some Saiyans, I firmly believe most of them got a greater satisfaction
from fighting/killing. Besides, while rape is used in wars, Saiyan's tactics were along the lines of "scorch and disintegrate" anything that moves.
Anyway... let's see what we know about Saiyan Relationships:
- When the Tsufuru-Saiyan War ended, Vegeta became King and a year later Prince Vegeta was born. They didn't lose time to get a heir, they were practical.
- Bardock seems to have kept the same "mate" for Raditz and Kakarot. Saiyan might seem to be somewhat monogamous. Tarble also seems to come from the same mother as Vegeta... a very small woman, I imagine.
- Females were seen hanging out at the Saiyan pub pretty much like Earthlings would do.
- Raditz mentions that Saiyans were already relatively few even before the planet's destruction. For a culture making a living of going to destroy other planets, I half expected a Baby Boom right after the Tsufur War, which clearly didn't happen. They were more interested on fighting than making sure to increase their numbers.
Now, Vegeta is our Saiyan walking manual. Although I consider him to be the extreme example his race's culture, let's see what he says about some topics:
When they learn of Gohan's power level from Raditz, Nappa suggest they make "a flock"
of hybrids with the Earthlings to start a new Empire. Vegeta quickly dismisses the idea saying that might backfire with brats too strong to control (Paragus knows this well). I'm pretty sure Nappa is not going to take female humans to a date (LOL), but the way he says it clearly is for a practical purpose, not because they are horny.
In any case, I doubt Frieza would have allowed the remaining Saiyans to "get some tail", as he was looking to get rid of the filthy monkeys.
In the manga, Bulma out flat says Vegeta and her were not together
, so she didn't know where he was. It's not surprising that the infamous 3 years are a paradise for the Fanfic writers, but most of the time they show how they fall in love... which I really doubt happen. I believe Bulma made an advance on Vegeta, because... well, Yamcha wasn't there? *shrugs*, and Vegeta just went along with it. That would explain why he didn't care at all about Bulma and Baby Trunks until after training with Mirai and him getting one-shot by Cell. I believe he did stick around for Trunks' sake... and for plenty of food and a roof. 9_9
Now, let's see Goku... he never ever showed any kind of attraction to anyone or anything that wasn't fighting. He did not know what marriage meant when he was 19. I'm positive he did not know what was going to happen in their bedroom, at all.
Depending on how Chichi handle it (no pun), their first time was either a very pleasant surprise or a complete disaster. Now, knowing Chichi and her obsessive idea to marry and have a perfect family, I bet she tried very hard to get pregnant right away. There's a funny fact about Gohan... Gohan was born on May Age 757, a whole year after Goku and Chichi married (May Age 756). That's about three months from the honey moon until his conception.
I bet the basics were laid out and the deed done, but I do believe she had to be the one initiating any encounter several days later as Goku is very oblivious regarding this stuff.
Saiyan might like to keep one mate just to avoid wasting time dating, but like to fight more than they like sex.