Does mc only says that he hooked up with stranger , to rile ml up or he actually hooks up then say.
Because i want mc to actually hook up, be loyal to someone who is giving u the same..its high time mc needs to wake up and fi d another male lead, or have fuck arround. Otherwise male lead just wont feel the agency that mc is ever gonna leave. Ml is so used to using mc, that i actually want him to know the consequence of his action.
Are u sure sure that male lead hooked up with his ex.
The start of S3 the ML is getting it on with his situationship (although it's not shown explicitly).
Towards the end of that chapter, the ML waits for MC, the next day at work but he doesn't showup.
The MC returns the day after hangover and chit chats about how since they are 'over' he went out drinking and met a guy through an app. ML had the audacity to think the MC was disgusting for it.
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Hopefully my explanation made sense.

S3 just started and I'm already about to drop...(╯°Д °)╯╧╧
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Seme goes and fuxks his situationship as soon as they returned and then has the audacity to feel some type of way, cause uke says he hooked up with some guy on a dating app afterwards.