Gemini and Leo make a sparkling, romantic, very vivacious combination. They work well together as signs. Now what Gemini is in astrology an air sign, meaning Gemini is curious and communicative and loves the sparkle of life, loves to explore, go out, be social, find new things to see and do. Leo is a fire sign, which means that it is looking for something magnificent, something that burns with magnificence. I use that word lot for Leo because Leo feels that he or she is magnificent.
They work well together because Leo needs a lot of attention and Gemini knows exactly how to give Leo attention. Gemini is very good in bed, loves sexual play, is wonderful at sparking a Leo to a great sexual performance.
Outside of the bedroom they also have a lot in common because they adore being with people. What Gemini likes about people is finding out new things, and Leo loves to get attention from people. In the middle of the relationship they do have to work out that issue of Leo needing so much attention, because Gemini may wander off.
It does have a flirtatious eye and loves to find new things, new people, not necessarily to go to bed with but certainly to interact with. Leo might get somewhat possessive and jealous about this. If they can work that out they can make a very good relationship, a good marriage, certainly a good business partners because what they do essentially is sparkle each other.