IDK why but part me think pigtail girl is partially lying about how she feels about ruri. idk her tone and body language felt like she wasn't telling the whole truth. IDK i could be wrong, but i feel like this might be a case where PT girl did start out hanging out with ruri cus she's part dragon, but slowly started to like her for who she is instead of being curious about her dragon parts. But as she looks at ruri as a real friend, i think she feels bad inside that the start of their friendship was not fully truthful, and she feels like their friendship was based off a lie. Again I could be wrong, but i could feel like this arc could end with them reseting their friendship to square one and starting over.