Noble

A noble is a quest-giver, a patron, a dinner host, an awkward escort job, or the cousin of a PC who just inherited a castle and has no idea what to do with it. The CR 1/8 stat block is almost beside the point. What you're running is a social encounter with a person whose Persuasion +5, Deception +5, and Insight +4 mean they're better at conversation than most of the party, and whose 16 Charisma will steer the room if you let it.

Use the noble as a vector. They want one specific thing from the party: protection on the road to the capital, recovery of a stolen heirloom, escort to a wedding they're being forced into. The job hook is the entire point of the stat block, and the noble's social skills mean they'll talk the party into it whether or not the party wants the gig. Lean on Persuasion +5 against the party's Insight to land the offer, then let Deception +5 hide whatever the noble isn't saying about why they actually need this done.

Combat is something the noble is bad at and knows it. With 9 HP, AC 15, and a single Rapier attack at +3 for 5 average damage, this is a glass figurine in a breastplate. The Parry reaction adds 2 to AC against one melee hit per round, which buys exactly one swing of grace before the noble crumples. In any real fight, the party should be protecting them, not standing next to them. Stage ambushes accordingly: bandits go for the noble first, the party has to peel them off.

The noble's most useful contribution to a road encounter is the network behind them. A sealed letter, a signet ring, a name dropped at the right gate. Make sure the party leaves the encounter with one of those tokens, and the noble will come back as plot in three sessions.

A noble as the antagonist of a scene is a duel of words with a sharp pin at the end. They are not going to brawl the party. They are going to insult one of them in front of the wrong baron, accuse another of theft at a feast, or invite the wizard to a private library and quietly steal her spellbook. The combat stats are the failsafe for when the social game ends with a drawn rapier.

Run the noble as a Charisma machine. Persuasion +5 to talk the guards into arresting the rogue, Deception +5 to swear blind they had nothing to do with the missing locket, Insight +4 to know exactly which PC has the shortest fuse and bait that one specifically. The party should leave the first scene fuming, with no actionable evidence, and a working theory that the noble is dirty. The next three scenes are the party trying to prove it.

If swords come out, it's because the noble has been cornered or because honor demands a duel. The Rapier hits at +3 for 5 average, which is laughable against a party of any level above 1, and the Parry reaction will save them from one hit. With 9 HP, the noble loses any straight fight in one round. Lean on Parry to extend the duel by one swing for drama, then have them yield with a knife at their throat. A captured noble who can be ransomed, traded, or testified against is worth more to the campaign than a dead one.

Give the noble a tic the party will remember. A signet ring twisted on the third finger when they lie. The party will catch it the second time, and the noble will know they caught it.