"Those of a different kind inevitably have different hearts; dragons indeed need to ally with dragons."
Leon has formed an alliance with Tassera, coming to a mutual aid agreement.
Leon has promised to help Tassera when she encounters enemies; of course, this isn't without limits. It's not like he'd go rushing in to sacrifice himself if the Blue Dragon provoked the Gods and got chased by divine enforcers. They're allies, not spouses. To put it bluntly, even if they were spouses, there are plenty of couples who sleep in the same bed but dream different dreams, ready to fly apart when disaster strikes.
Conversely, if Leon finds himself in danger, Tassera also has the obligation to help. Besides this, should Leon have other needs, such as wanting to set up Magic Traps in his lair, or wanting a few Stone Magic Statues as lair guards, she must provide assistance too, and of course, she cannot forgo her fees. He could pay with money, or with knowledge.
