how do drow, long lived even for elves, keep their population from exploding? their cultural tendency towards less promiscuous behaviors helps (the drow are much less likely to engage in casual physical contact, so being chaste in general often follows), but the real answer is simple: they have very infrequent heat cycles, and are otherwise usually not fertile except for at this time.

the Shadowhand has been suppressing his heat for some time now, but travelling with the Mighty Nein, it slips his mind for just long enough... and once its started, there is no putting the lid back on it. he admits his situation to the concerned Nein, and one of them offers to help.

+anything goes pairing wise, and it can be platonic or romantic. I think it'd be fun to see something less common like Mollymauk and Essek, but your more typical Calebssek is okay too!
-no noncon or dubcon please! Essek should still be able to consent. maybe the heat makes him uncomfortable if ignored, but no one feels forced to help, they're actively choosing to do so (likely to Essek's surprise; maybe he expected to tell them he'd be indisposed and wait it out on his own?)
+if you are partial to heats that make someone near incoherent with lust or a begging mess, that's fine as long as Essek still consents at the beginning and those involved are aware of boundaries (maybe Essek gives permission in advance to magically restrain him as necessary if he gets too lost in his heat and they want to stop?)
+as a fun note: the drow height range is 4'6" to 5'5" canonically. perhaps that's something you want to play up?