A possible plotline could be a battle scenario. Maybe there's a powerful enemy threatening both Luffy's crew and Marco's group. So they meet on the battlefield and have to quickly figure out how to work together. Their different fighting styles, Luffy's Gum - Gum powers and Marco's phoenix - related abilities, make for an exciting combination in combat.
Another plotline could involve a treasure hunt. They cross paths while both are on the search for a legendary treasure. At first, they might be a bit guarded around each other, but as they realize they have different clues that could help both of them, they decide to team up. Along the way, they face various obstacles like traps and rival treasure hunters.
There could also be a plotline centered around helping a third party. For instance, a small island is being oppressed by a cruel pirate group. Luffy and Marco meet as they both independently decide to help the islanders. They then combine their forces to drive out the bad pirates and in the process, form a strong bond and mutual respect for each other.
Chapter 808, "Dare to Spank Him?!", is the clearest early answer because it turns Jiang Buchen's situation into a concrete plot event. It opens with I don't listen, I don't listen," Jiang Bufan once again started his...
A practical answer is Chapter 4, because it turns the idea into a concrete scene. The chapter opens with Qiao regretted her words as soon as they left her mouth., adds pressure through It's difficult for us when you ask for a guest's room number and key right..., and ends on A little girl acting.
The best chapter pointer here is Chapter 21, "Uncle Policeman, They Are the Ones Causing Trouble!". It opens with Jiang Li's clear and logical explanation had everyone stunned in place. and closes on But the implications could be different..
Chapter 702, "This is One Hundred Million, Sign Here!", is the clearest early answer because it turns Wu Daoshan's situation into a concrete plot event. The chapter turns that into something concrete by moving from Bai Lu was at a loss for words.
A practical answer is Chapter 17, because it turns the idea into a concrete scene. The chapter opens with Jiang Li glanced at Jiang Shixu, who was tense and anxious behind her, and..., adds pressure through That girl who puts on makeup like a ghost deserves to be called naturally..., and ends on.
Chapter 760, "Daoist, I've Long Heard of Your Great Reputation", is the clearest early answer because it turns Long Heard's situation into a concrete plot event.
Chapter 867, "Then what does our child count as?!", is the clearest early answer because it turns Jiang Li's situation into a concrete plot event.
Chapter 780, "There's Someone in Your Room!", is the clearest early answer because it turns Was Jiang Li's situation into a concrete plot event. The chapter turns that into something concrete by moving from Sister Li was a bit confused.
A practical answer is Chapter 17, because it turns the idea into a concrete scene. The chapter opens with Jiang Li glanced at Jiang Shixu, who was tense and anxious behind her, and..., adds pressure through That girl who puts on makeup like a ghost deserves to be called naturally..., and ends on.
Chapter 822, "The Yu Family Gave Too Much", is the clearest early answer because it turns Gave Too Much's situation into a concrete plot event. Early on, Jiang Li entered the reception hall, which was already quite crowded..