Brendan was lying down in his emerald boxers with the white Pokemon logo like May's bandana. He was on the guest bed in Mr. Briney's new ship on the way to Jhoto with his renewed significant other May in her quest to become a top Pokemon Coordinator.
May had just wrapped up a special contest in the Shinoh region, coming in second against her old friend Ash's new squeeze Dawn.
May had a little interest in Ash, but her "new neighbor" back home Brendan had set off on his own quest to become a Pokemon master with a Mudkip, now a Marshtomp, he got from his father Professor Birch. He ran into May several times along the way, where his interest in her definitely showed significantly.
These are just a few of those times:
One time, he was at the beach when May and her friends showed up. He tried to play it cool as he walked up to her to say hi in his trunks... but his heart skipped a beat when she cheerfully said "Let's go swimming!" to no one in particular... and began to quickly strip in public!
"Hold on May!" her brother Max, who was also traveling with her yelled "you can't take your clothes off on the beach!"
To her friends relief and Brendan's disappointment, she had green swimsuit with extra trim on the top underneath her clothes. May looked stunning in it.
Brendan showed up, unable to control the reaction on his face (as well as other body parts) or respond to May's greeting before she ran off, racing the gang into the water.
"Hey Brendan," Ash asked "how'd you get over here so fast?"
Brendan whispered behind his hand "...I heard 'May', 'clothes', and 'off' in the same sentence."
"Sigh" Max emitted. "Is he trying to hit on my sister again?"
Max had trouble understanding what Brendan saw in his sister, but he still thought highly of him and his other new friends and traveling buddies. Brendan always insisted to him he would never try to use her sister and that he genuinely cares for her, not just as a love interest but as a friend and person. This helped to put May's little brother at ease, and he tried to help Brendan whenever he could with May, just as he tried to help him, answering any questions for when he would finally get his first Pokemon.