[Nacht]

My take on what the flying horros are actually like, based on the images shown in the post-timeskip PTP4

[Nacht]

First capture attempt

[vitus]

Good work, hm, there is no thumb up icon with smilies...

[Nacht]

Crappy quality, but a first attempt at riding gear. Stirrups are missing though.
Since these are birdlike creatures I imagine carrying us would already be a challenge, so heavy gear (e.g. metal, breastplate) would not be possible. Instead everything is light leather, minimal gear for minimal weight.
Depending on how intelligent these creatures turn out to be, we could very well design armor for them to wear independently of a rider.