The first-person pronoun clearly expresses the speaker's viewpoint, as it is the pronoun speakers normally use to refer to themselves.
This verb appears to express the listener's viewpoint. 'Come' is a deictic verb, which normally expresses movement towards the speaker (as in 'Come here!'), and contrasts with 'go', which usually indicates movement away from the speaker's starting position (as in 'I'm going to London tomorrow'). But, here, 'come' is used to refer to the speaker's future movement towards the hearer and, so, is an example of the speaker taking his hearer's viewpoint into account. We will deal with deixis in more detail in the 'Linguistic Indicators of Point of View' page.
This represents the speaker's viewpoint in the continuum. It represents close future time, i.e. the day after the speaker is actually speaking. If you compare 'tomorrow' with 'the next day', for example, you can see that 'the next day' represents a following day in some more remote future sequence of days.
The second-person possessive pronoun 'your' clearly expresses the speaker's viewpoint in relation to the listener (we used the second-person pronoun to refer to those we are addressing). But the noun 'sister' expresses a kinship relation between the hearer and someone else. So the speaker is effectively expressing his own viewpoint and taking that of his listener into account in the same phrase.
This diectic adverb clearly expresses the speaker's viewpoint. As he is in a coffee bar when he speaks, he expresses a relation of distance with his friend's home (he would use the contrasting term 'here' to refer to the coffee bar he is sitting in). As the listener is also in the coffee bar, 'there' is also appropriate for him.