Neville might also be a regular. He'd come to the cafe to relax after a long day of herbology classes. He could sit in a corner, sipping on a 'Mandrake Mint Tea' and perhaps chatting with other students about the latest plants he's been working with.
The Weasley twins could be regulars too. They'd be interested in seeing if there are any new magical concoctions on the menu that they could get inspiration from for their joke shop products. Maybe they'd sample some 'Fizzing Coffee' to see if they could create a similar fizzing product for their shop.
Hermione would probably be a regular. She'd come to the cafe to study while enjoying a warm cup of Butterbeer latte. She might even bring some books from the Hogwarts library to read there.
I bet the regular customers would include some of Harry's old Hogwarts friends. Maybe Ron would stop by for a butterbeer and a chat. Hermione might come to relax after a long day of research. And of course, the Weasley twins would probably be there often, looking for new business ideas or just to have some fun.
His old ninja friends like Sasuke, Sakura could be regulars.
Students from Hogwarts could be regulars. They might come during Hogsmeade visits. Also, young wizards and witches starting their careers in Diagon Alley would stop by. And of course, some of the older professors might pop in for a cup of their favorite brew.
His old friends from Hogwarts would surely be regulars. Ron and Hermione would be there often. Neville might come to relax after a day of teaching Herbology at Hogwarts. Luna could drop by to share her latest theories about magical creatures while sipping on a strange - looking drink. Hagrid might also be a regular, though he'd need a special - sized chair.
His old friends from Hogwarts like Hermione and Ron could be regulars. They might come to support Harry's business and also to buy some useful things for their own magical lives. Maybe Neville would come to buy some special plants for his own gardening projects.
I think magical creatures would also be customers. Maybe house - elves would be sent to pick up treats for their wizarding families. Hippogriffs might be lured by some special bird - shaped pastries. And even centaurs, if they were feeling a bit more adventurous, could come to the edge of the Forbidden Forest where the bakery might be located to get some goodies.
It could be that they use magic to keep the pastries fresh all day. There might be a charm placed on the display case that constantly renews the freshness of the cakes and muffins. Something like 'Freshio' charm which ensures that every bite tastes as if it was just baked.
Hermione would definitely be a regular. She might come to the bar to relax after a long day of studying ancient spells at the library. Ron would also be there often, enjoying Harry's special butterbeer with extra foam. Hagrid could be another regular, coming in for a large tankard of a strong, warming drink.
Other potion shop owners might visit too. Not as customers in the traditional sense, but more to check out the competition. They might be curious about Harry's unique potions. And then there are the local wizards and witches in the area where the shop is located. They could need potions for daily life, like a potion to make their gardens grow better or a potion to keep their pets healthy.
Well, the regular customers could include some of Harry's old friends from Hogwarts, like Ron and Hermione. They would support Harry's business and enjoy the unique atmosphere. In addition to that, supernatural hunters from the Supernatural world might stop by. They could be looking for information about certain supernatural beings that might be lurking around the bar. And of course, there would be the local supernatural community, such as witches and warlocks who are not directly related to Hogwarts but are interested in the mix of magic and the new - found supernatural elements in the bar.