Good writing is good writing, however this scene would not have worked in an actual game.
GM: Tarkin turns his back to you and walks up to a stool holding a tray of wine.
Elan's player: Attack of Opportunity.
GM: WHAT?!?!?
Elan: He's walked out of my threat range, so I attack. Since I have combat reflexes I get another attack of opportunity when he picks up his drink. Since it's a surprise attack and since he is unaware, he is flatfooted and will remain so until the end of the surprise round, which starts after I make my second attack. Oh yeah.. I'm going full attack so, that's three attacks this round (I'm assuming Elan is atleast8th level). Since I'm attacking him from behind, do I also get an attack bonus along with his being flatfooted?
It even would be worse if he Elan had rogue levels or a firearm.
a) The PC has been disarmed (and probably humiliated). And we've already established that the PC barely has a chance to hit Tarquin with a weapon. Even if the PC had another weapon, he'd have to draw it, which would eat up a surprise round and the PC's backup weapon is unlikely to be as effective as his primary one. A PC in this situation is far more likely to let Tarquin leave the threat range and then try to cast a spell, since Elan is a bard afterall. However, Charm Person and similar tricks that Elan might know are unlikely to help here, since Tarquin's demeanor to Elan is already Friendly (at the least). Likewise, illusions or other distractions to help Elan escape are pointless, since Tarquin is willing to allow Elan to escape.
b) We've already established that Elan believes he is a hero and believes he must conform to certain narrative expectations regarding being a hero. This prevents Elan from trying to kill someone who has just spared his own life, since to do so would make Tarquin narratively the hero and Elan the villain. Thus, your action is out of character for this particular PC.
c) Even if Elan succeeded in the attack, at most tables (mine certain) this would necessitate an alignment change for Elan since he can't both violate his own code of morality (kill someone who has spared his own life, much less his own father) and maintain his own view of himself as the hero. Elan knows that this is exactly what Nale would do (and in fact has done!) in the same situation. As such, this would mean Elan becomes a villain, and Tarquin - in a perfect Xantos gambit - would then be able to claim that his victory is made more perfect because Elan has become the treacherous son he always wanted him to be.
d) Your player doesn't even have the rules correct. This can't be a surprise attack since Tarquin is aware of the PC. At best, the PC could demand another roll for initiative, but very likely Tarquin is only feigning dropping his gaurd (since earlier he learned that Elan has [off]spring attack skills) and is prepared for any such action by Elan.
e) Tarquin has previously shown that he's extremely alert and generally never caught off gaurd by 'surprise' attacks. It's possible for example that he has a feat that let's him take the Full Defensive action even when its not his turn, or some other ability (like Uncanny Dodge) that let's him retain AC when flatfooted. In all likelihood, any further attack by the PC would be no more successful than the previous futile attacks.
