What happened to sayo's arrows? Has she lost her love?
You know, that would make for a VERY shocking twist. But most likely the artist simply forgot to add them in.
Possibly.
Another theory is that she's a little confused by the accidental kiss and maybe isn't certain where her love is at the moment. The arrows do seem to show up in full force when emotions are involved so if someone isn't actively feeling at that moment, they simply may not have any arrows. (Like if they're thinking about doing homework or having to clean the kitchen instead of the person they love).