Yeah I'm still under the idea that while she does have a crush on Mason, she might be looking for some kind of stability in all this mess because she's had more bad happen to her than good since the comic started.
If we count her flashback then within the span of possibly a month Sesame has
-Had her village burned to the ground over what seems to be a weird scarf.
-Lost on of her last two remaining family members
-Lost her fire sword due to overconfidence.
- Nearly gotten her arm bitten off.
-Had one of her friends framed for murder.
-And she's stuck with some weird gauntlet that keeps screwing her mind when she sleeps by showing her alternate timelines/dimensions/and whatnot. She even saw a version of herself cut open.
All and all shit hasnt been good for Ses and big ol Mason is looking like a fine rock of stability to her