While "suitor" implies someone who is romantically pursuing another, there are other words that capture aspects of that pursuit:
* Wooer: This emphasizes the act of trying to win someone's affection.
* Courter: This focuses on the formal and respectful nature of the pursuit.
* Adorer: This highlights the intense admiration and love felt for the object of affection.
If you're looking for a more casual word, you could use boyfriend, girlfriend, or lover depending on the context.