I have been researching to create a character background in D&D 5e of a Draconic bloodline sorcerer Tiefling noble (a stretch I know, but I have an idea to make it work). I cannot seem to find a description in any wikis of followers of Bahamut other than dragons. I am not set on making him religious, but it would help my character in his drive to be a better individual, and bring honor to his now-disgraced house. I am wondering if there is any other info in other material I do not have access to about the followers of Bahamut.
Just because you want your character to be a follower of Bahamut, that doesn't necessarily require all his people to follow Bahamut.
For example, he could have been rescued by a follower of Bahamut, he could have had some kind of vision, he could have touched a holy relict of Bahamut that created a special connection between them, etc etc etc.
Also, your character is a Draconic Bloodline Sorcerer, that's a ton of story hooks available right there, depending on the background story of why that's your bloodline.
Although, as a side note: depending on how much you want to go Bahamut, the Divine Soul Sorcerer from Xanathar's Guide To Everything, page 50, might be relevant for you as well.
Anyhow, the bottom line is: think outside the box.
Just because your character isn't a dragon (for obvious reasons) or a Dragonborn doesn't mean he can't be a follower of Bahamut. There might be some lore out there about non-dragon(born) followers of Bahamut*, but the easiest solution is to just create it yourself!
*I'm pretty sure that'd be previous editions, though. I don't think something like that is mentioned in the 5e rulebooks.
I'm currently updating an old 2e character who adventured in Krynn (Dragonlance) and was a cleric of Paladine. Paladine is so much like Bahamut (and, in fact, one of the names listed for Paladine in Krynn is Bah'mut). Whether or not Bahamut and Paladine are the same entity is actually something of a heated debate, but I figure, at the very least, they would be on friendly terms, so if a Krynnish cleric of Paladine entered another realm where Bahamut held sway, that Bahamut would accept the cleric as one of his own ... and that's assuming the two entities are not different projections of the same entity.
So, in your case, you might look into the old Dragonlance lore and base your cleric on Paladine. Having just went through the process, I can say it was a bit time consuming to figure out which spells he'd have access to when there was no obvious equivalent in the 5e lore, but I did it, and I like the results.
Might be something to consider. However, I completely agree with the "bottom line" in PixelMaster's answer.