If you dont want to breed, then dont put them together, because they will breed wether you like it or not 
Your best bet is to get another dragon and raise them separately, houseing multiple dragons of any sex combination is an iffy idea...here is a little something i wrote as to why..
1. Dominance Aggression/Stress: Many people make the mistake of assuming that aggression is displayed only through head bobbing, throat puffing, and physical attacks, but this is incorrect. While its true that these are SOME of the ways that dominance/aggression can be shown there are other, subtler, and probably more dangerous (because they can be harder to notice) ways. Usually when two beardies are housed together, even females, one of them will be more dominant than the other one, the more dominant one will usually take the best basking spots and the most food. Getting less food and taking second best basking spots chronically will become stressed; chronic stress will lead to failure to grow and thrive and parasite infections. Even if the more dominant beardie doesn't "take" the most food, their presence will often lead to the less dominant one not eating us much. A good analogy is to imagine you are back in school, you are sitting down, about to eat your lunch and the class bully plops down right next to you to eat his lunch...you are probably going to lose your appetite. Right? Now what if that happened every day? Sometimes if the two are together the more dominant one will bask sitting on top of the less dominant one, many people will mistake this as a sign of affection, and think that the BD's are friends, but its actually a sign of dominance. The biggest issue with dominance aggression is that it leads the other beardie to always be stressed, and over time this will cause his immune system to falter and will allow for parasites to multiply in the system. You will often hear people say they have had two beardies together for some time with no problems and then one of them grew much bigger while the other stayed smaller...this is typically what happens, if they are not separated and treated the smaller one will usually end up dying.
2. Physical Aggression: Not much needs to be said about this, physical aggression is when they actually fight. Chasing, biting, scratching etc. Obviously this leads to drastic problems such as stress, infections and lost limbs. Sometimes beardies will appear ok with each other for months or even years and then one day they begin finding.
3. Positive Sex Identification: This is a problem that frequently gets over looked when people consider putting two dragons together. Dragons cannot be sexed 100% until they are close to a year of age. Educated guesses can be made, but without probing there is no sure fire way to tell. There are a few problems that can arise from this. If you get two baby beardies and house them together and they turn out to be a male and a female and you don’t notice in time they will probably mate, and probably when they are two young. Mating when they are too young causes serious problems for the female, producing eggs takes a lot of nutrients and energy...energy that young dragons need to be using to grow. Young dragons that are bred are more likely to get sick or become egg bound or have other problems related to reproduction. If it turns out they are two males, the beardies may be able to tell before you do and you could come home one day to find they have been fighting. It’s possible that one may even kill the other.
3. Disease, spreading and identifying: Another issue when dragons are housed together is disease. First and most obvious, if one dragon gets sick, its housemate is going to get sick also and then you will have two dragons to treat, not just one. Also, say you come home one day to find a suspicious looking poo (smelly, runny, and nasty) or some vomit, there is no way to tell which dragon is having a problem, unless you can constantly observe them. Or, how do you tell if they are both defecating? If one dragon was to become impacted (or has another issue causing constipation) you may not be able to tell until it’s too late. You will still be seeing fecals, but will be unable to tell which dragon they belong to. Also, one early symptom of disease is lack of appetite, when beardies are housed together its harder to tell who is eating how much. This is especially true if you keep veggies in the tank constantly, or often. You may set out the salad, walk off, come back later and find it all eaten...but who has eaten it? There is no real way to tell, you may not notice one dragon isn't eating until you see significant weight loss.
5. Space: This is another big one. More than one beardie means you have to double or triple the space. For one adult beardie the minimum cage size would be a 55gallon (although 75-90 is ideal). If we are talking aquarium gallons, a 125g is the smallest I would ever consider housing two beardies in.
There are other reasons as well why its not such a good idea, but these are a few of the biggies. I am not saying that it cannot be done, but it presents a whole new world of issues to deal with. Keeping multiple beardies is best left to the experts, or at least those who have a bit more experience with beardies. People with more experience may be able to identify potential problems quicker and intervene before a problem becomes serious. If multiple beardies are housed together you should definitely wait until they are adults that are proven females, if you buy two babies keep them separate until they are full grown and then maybe work on integrating them. And always, always, always have a second enclosure available should you need to separate them.
Personally, I wouldn't take the risk. Beardies are awesome lizards but they are definitely a handful and caring for two in the same enclosure just makes it that much trickier.
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0.1 Bearded dragon (Hannabil)
0.1 mexican Black kingsnake (Morticia)
2.1 Leopard Gecko's (Pogo,Jeffrey Nothing, Louise)
0.0.1 Tokay Gecko
0.0.1 Reverse Okeetee Corn (Autumn)
1.0 Blood Red Corn (Virus)
0.0.1 Mali Uromastyx (Scuttle)
0.1 Bullmastiff (Asha)
4.1 Cats (Poe, Tucker, Abhid, Felicity, Emmy)
