Ren as the main attacker, Mei as active back-up

There was no time to lose, and the situation was too out of hand for either of them to hold back.
Ren still wouldn't let Mei take the main role considering her damaged cultivation, but still hinted her to not hold back while fending those critters least they get overwhelmed by their numbers.

There wasn't much of a plan, only kill, kill, kill and again kill till all of them were dead!

Ren unsheated his sword and beheaded a jumping Jaki, kicking then another aside while stabbing a third jumping one, though he still couldn't fend off the two behind him and ended up with a Jaki clinging to his leg in an attempt to bring him down and another jumping on his back with his claws attempting to rip his eyes out from behind!

It was a precarious situation, but still not as bad as Mei's... being a female, most of those vermis threw themselves straight at her and if it wasn't for her actively using her energy to fend them off and bash some dead while she was at it, things may have been much more precarious.

At least their number wasn't too large, though most of them were evidently aroused... the tingle in her loins reminded her of what she heard of the critters.
Jaki would release a kind of arousing miasma whose power depended by their energy and lust. A single Jaki, even horny, wouldn't pose any threat but... well, it was unwise for a girl to fight against a large number of horny Jakis.
One's own cultivation could help offset the miasma's effect, but the larger their number the harder it'd be to resist.

Maybe if she didn't actively use her energy she'd be more affected... but she did, and the little demons had nothing on her.

It took some time and there were some dangerous moments for Ren, but eventually all the ambushing demons were dealt with and the couple managed to scavenge 12 coins worth of demon cores, a decent gain though this could only be considered a shallow victory due to how much energy Mei had to waste to fend them all off.

[Mei Qi decreased by 20]