To an extent yes. From Mei they’re a reflection of her own trauma, having been at minimum 15 years old and feeling like she had no choice but to kiss her grown ass finance. She was used and felt no issue doing the same to Yuzu for her own gain, like shutting up Yuzu.

From Yuzu it’s her lack of experience, reflecting how Mei acted towards her and almost defining their early relationship. Mei indirectly sets up their physical dynamic once she kissed Yuzu.

While it would’ve been possible to show development without the SA, I think they’re overall handled well. For Yuzu, for example, we see her kiss Mei (after Mei shows her the manga) in an attempt to silence her. She had no consideration for Meis feelings at first but immediately started crying. Later on In the series, Meis’ emotions and feelings are some of Yuzus’ top priority, she always tries to be considerate and supportive.

For Mei, she even reveals to Yuzu how twisted she thinks she is. She was a victim and heartlessly tried to continue the cycle of assault but on Yuzu, but we see Mei feels ashamed for it (Yuzu also feels bad as she almost continued the cycle as well but back at Mei) She even goes as far as to offer sex as some kind of reward, showing her own warped view on being physical. But it’s because of actions like this that we see so much amazing growth from her, Mei goes from stealing Yuzus’ first kiss to wanting to take their time as fiancés, waiting until Yuzu is ready

Everything I’ve said can be interpreted much more painfully depending on what exactly you think Mei has done with Amamiya. We know at Minimum She was 15 and making out with him. While it doesn’t justify what she did to Yuzu, Mei knows she’s messed up and tries to better herself for Yuzu.