All I can say is that the small guy seems to be their weak spot, but without some sort of cheesing I wasn't able to exploit it properly T__T

"Quick-and-dangerous-yet-effective" way:
1. Dodge through them.
2. Turn around immediately.
3. Jump and try your hardest to hit that little imp with only one melee strike.
4. Land and prepare to dodge immediately.
5. Repeat until defeat (hopefully their). Should take only 3-4 hits (with all dmg ups available at this point).
"Slow-and-tiresome-yet-kinda-working" way (works only if there are walls and/or high ground available):
1. Wall-jump repeatedly/stay on high ground.
2. Land on, well, "low" ground; time your landing with beginning of enemy's jump (away) animation.
3. Do one full-stamina bow shot.
4. Get back to the wall/high ground, waiting for stamina's refill.
5. Repeat until defeat (hopefully their). Should take only 2-3 minutes (with all dmg ups available at this point and if you won't get tired from repetitiveness of ordeal).

I'll give those a try! Thanks. I always get up to the part where I HAVE to fight one, and he manages to smush me every time, hopefully I can manage it with some practice