(NB: D.T. stands for doutei 「童貞」, basically "virgin")
Physical activity expands energy; cultural activities conserve it. Since that energy is used in delusional thoughts, creative things are born. *
Surely Lelouch's rebellion was a karma that confined him to remaining a virgin*. Even though he was surrounded by nice bodies and cute heroines (C.C., Karen, Kagura, Viletta..), instead of turning his eyes to them, the passion that is characteristic of 17-18 year-old youths was instead spent on his rebellion.
Just as he was called an "overthinking virgin boy" (「頭でっかちの童貞坊や」, courtesy of C.C. in Stage 13, IIRC), he (probably) persisted in it unwaveringly. His unending energy source for the rebellion came from his D.T. life.
Whilst it is a pity, he probably met Zero Requiem in that manner. Was he perhaps the first D.T. Emperor of Britain (at any rate, it is said that Emperor Charles D. Britannia had 108 wives). Emperor Lelouch may have conquered the world, but until the end, he was never able to conquer a woman.
By all means, as an honourable virgin, he will still be a hero talked about through the ages hereafter. *
Evidence for Lelouch's D.T. status
1. (You) wanted to say this line at least once!? A completely cliched (pick-up-line)
Having been betrayed by Nunnually (Turn 7), he turned to Karen and deliberately intoned "Comfort me. Since you're a woman, that's something you can do, right?" Probably, having read this somewhere, he thought that he should try them. Is that not something an inexperienced person would do, a pattern of someone who always follows his (big) head? A character who is used to women would not have said such a line - he would probably have just moved in on her. (笑)
2. Not understanding the subtleties of youthful love, unthinkingly asking Shirley!?
The secretly disturbed Zero (Lelouch) who found out about the ostensible romantic feelings between the Chinese Federations Xing-ke and Tianxi: whilst lost on what to do, Lelouch received an unexpected call and advice from Ashford Academy's love master, Shirley. Shirley's answer was that "Love is power!". In his second-hand retelling, this became his "thoughts are a power strong enough to change the world" speech to Xingke...
3. He diligently fulfilled those dates seriously, but leaves only the impression of ackwardness
Sayoko, acting as Lelouch's double, set up a mountain of dates with the girls of the Academy. Although Lelouch voiced his complaints to Sayoko, he conscienciously went on all of them. On top of that, he did it without become closer with any of them! just as one would expect from someone without any experience. With the rebellion to consider, time for dates might be pointless. Even though, since all those dates were set up, it would have been better to spread his wings (in this case). The world cries at just how bad he is with women.