It takes a long time to evict someone and you should not try and do it without a lawyer's assistance. What does your lease say about long-term guests? You may have a way to get the boyfriend out, but, again, you really need a lawyer's assistance.
In the meantime, if you think the dog is being neglected, call animal control.
You may evict a tenant at any time so long as there has been a breach of the lease or the lease term has ended and a notice to vacate has been provided.
To evicty, you must file an unlawful detainer action. Generally, such cases can be heard within the month and do not take long to process under Minnesota law.
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